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1242: Off I go then. Let's hope tomorrow's quarter-finals live up to expectations. Suarez-Navarro v Dementieva kicks us off at 0000 GMT, followed by Kuznetsova v Serena and Verdasco v Tsonga. From 0830 GMT, UK viewers can watch Nadal v Simon on the Red Button or on this website or listen to it on BBC 5 Live sports extra. Failing that, you'll just have to put up with me.
1238: That is 19 consecutive Grand Slam semi-finals for Federer. I hope Andy Roddick had an early night and missed that performance.
1236: Federer looks a bit embarrassed to celebrate that. A consummate display from the former world number one, albeit against an opponent who gave up rather too quickly.
Federer 6-3 6-0 6-0 Del Potro
Federer's 11th and 12th aces take him to 40-0. Del Boy makes one final stand by saving one but then nets a forehand. Fed through to face Andy Roddick on one hour and 20 minutes.
1233: "Roger... show some mercy!!"
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Federer 6-3 6-0 5-0 Del Potro
A winner! From Del Potro! Blimey, I wasn't expecting that. Federer frames a return into the trams to make it 30-30 but then takes charge of another baseline rally. Ruthless. He puts an effortless forehand into the space and Del Potro will have to break serve for the first time if he's to avoid a double bagel.
Federer 6-3 6-0 4-0 Del Potro
The Australian crowd - the ones who haven't left already - are starting to get a bit annoyed with this. Del Potro barely challenges in that game and he has won three points in this set.
1227: "What is happening to Del Potro, does he have a heat problem like Djokovic?"
giantTutu on 606
No, just a Federer problem - like a lot of players.
Federer 6-3 6-0 3-0 Del Potro
Horrified gasps as Federer's return clips the net - and doesn't go over! That's one break point gone but Del Potro's 21st unforced error gives Fed the double break. Unquestionably a masterclass from Federer, but Del Potro seems to have given in, which is a sign of a bit of inexperience.
1224: "Is JMDP just a flat track bully? He always seem to struggle against the very top players."
Anon via text on 81111
Federer 6-3 6-0 2-0 Del Potro
Both players in a hurry to get off court. Expect a massive cheer if Del Potro manages to win another game first.
Federer 6-3 6-0 1-0 Del Potro
Del Potro needs a good start in the set, but doesn't get it. He does as I would do in this situation - begins to belt the ball as hard as possible. It doesn't work for poor old Del Boy either and he is broken to love. As Del Potro's last desperate shot - which bounced twice - comes over the net, Fed fakes to smash it before nodding it over with his head. The crowd loved that. Not sure Del Potro did.
Federer 6-3 6-0 Del Potro
I wouldn't blame Del Potro if he did a Djokovic here. He looks embarrassed to be out there as Fed serves out a near-perfect set to love. Andy Roddick is waiting for the winner of this match in the semi-finals... which, let's face it, will be Federer. The American ended a run of 11 straight defeats against the great man in Miami last year. If Fed plays like this though, I know who my money's on.
Federer 6-3 5-0 Del Potro
Another game, another break point. Del Potro running blindly to the net before seeing the ball come right back onto his toes, forcing him to net the volley.
1211: "Re Federer's two quarter-final defeats: One was to Safin in Wimbledon 2001 after he had just ended Sampras run. Can you tell me when did he lose his other QF?"
VS via text on 81111
That's probably the first time Tim Henman has been confused with Marat Safin. Henman beat Federer at Wimbledon 2001, Alex Corretja beat him at the French in the same year. Those are the only two Grand Slam quarter-finals Fed has lost, winning the other 20... about to be 21.
Federer 6-3 4-0 Del Potro
Federer ignores the wolf-whistles as he changes his shirt. He's probably smiling inside though. Another mind-blowing half-volley earns him the first point and it's plain sailing from then on. He has hit 21 winners and made seven errors so far. Del Potro's figures are 10 and 15.
Federer 6-3 3-0 Del Potro
Under pressure to do something - anything - with his serve, Del Boy double-faults. That's 0-30 and danger time. An ace gives him hope but then Fed fires a return winner to earn two points for the double break. Gasps of disbelief as Fed puts a passing shot - a very difficult one - into the net. On the second, Del Potro's serve out wide is called out - but HawkEye comes to the Argentine's rescue and it's an ace. Fed looks stunned. JMDP seems to have an easy put-away at deuce but faced with the brilliance of Federer, he pushes it wide and Fed does break again.
Federer 6-3 2-0 Del Potro
Federer has lost two of his 22 Grand Slam quarter-finals, announces BBC Sport's Sam Smith. Let's hope Del Potro doesn't know that.
Federer 6-3 1-0 Del Potro
You can almost see the belief draining out of Del Potro. He is rooted to the spot as Fed plays an exquisite drop shot to make it 0-30. Three break points follow and Federer takes the first with most ridiculous half-volley drop shot. It's a masterclass from the 13-times Grand Slam winner. If you're already starting to think about tomorrow's action, I can tell you that UK viewers will be able to watch Rafa Nadal's quarter-final against Gilles Simon from 0830 GMT on the Red Button and on this website. Commentary on 5 Live sports extra.
Federer 6-3 Del Potro
Fed bangs down two aces to get to 30-0 but is denied a hat-trick by a netcord. He quickly earns three set points, but a couple of mistakes give Del Potro a bit of hope. That hope dies when a wrong-footing backhand forces Del Potro into a mistake. A quiet but firm "come on" from the three-times champ.
Federer 5-3 Del Potro
That'll help. A big serve gets Del Boy to game point and Fed obliges by putting a backhand just long.
1144: "Federer's back!"
Chazfazzer01 on 606
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Federer 5-2 Del Potro
Del Potro hammers a huge return almost onto the baseline, but Federer rocks back and nonchalantly half-volleys a forehand down the line. Genius. A hold to love.
Federer 4-2 Del Potro
Federer looks a little complacent as he flips a cheeky half-volley into the bottom of the net. He's back on track on the next point though, stroking a backhand crosscourt to make it 30-15. Del Potro stops the rot by firing down his first ace to hold.
Federer 4-1 Del Potro
Del Potro has never won a match or even a set against Federer - and looking at this, it's not hard to see why. The Argentine doesn't appear to have anything to trouble the world number two. His only hope might be that Bad Fed - the one that scraped past Tomas Berdych in the last round - reappears. No sign of him at the moment as the former champ holds to love.
1135: "Doesn't Federer look GORGEOUS?"
Phil, Baker Street, via text on 81111
Federer 3-1 Del Potro
JMDP sticks a backhand into the trams on game point. After a long consultation with himself, he challenges - wrongly - and then faces a break point as Fed takes control at the net. The second seed is given what looks an easy passing chance - but can't take it. Del Potro has chances to take the game, but Fed hangs in there and has another break point when he hammers a forehand onto the sideline. The pressure tells and Del Potro fires long.
Federer 2-1 Del Potro
Del Potro looks angrily at his foot as he stumbles while hitting a forehand. Federer loses just the one point on serve again.
1121: "Del Potro is 90% arms and legs. Fact."
jonnyfedfan via text on 81111
Not sure about fact, but I see your point.
Federer 1-1 Del Potro
Huge groundstrokes from Del Potro which isn't normally a problem for Fed, but even the Swiss is rocked back and nets a forehand. Del Potro holds to 30. By the by, John Lloyd has been looking up the stats and reckons Djokovic has now pulled out of seven matches in his career - including four in Grand Slams. As Lloyd says, that's not a great message.
Federer 1-0 Del Potro
Federer drops the first point but reels off the next four with the minimum of fuss, swiping a backhand onto the baseline to seal it.
1114: Del Potro won the toss - but elected to receive, which seems an odd one. So Fed will get us going.
1111: "Playing at night is a big boost for Federer. He's only played one day match and he nearly lost it against Berdych, but he won't play another one now. I think the faster daytime conditions would have suited Del Potro. I think Del Potro might sneak a set here but I can't see Federer losing."
BBC analyst John Lloyd
1107: "How are you?" enquires the umpire as Federer strolls to the net for the coin toss. "Good. You?" responds the ever-polite Swiss. This is Federer's 23rd Grand Slam quarter-final and his 19th in a row so no wonder he's so relaxed. Del Potro is in his second.
1104: On to today's final match between second seed Roger Federer and Argentine Juan Martin del Potro. "I will play the best player ever," says Del Potro on his way down the tunnel. "But I will just have to do my best to beat him." Here's Federer's verdict: "I hope I can get off to a better start tonight than I did against Berdych because I think that's going to be key."
1100: Just after ending her interview with former pro Alicia Molik, Safina grabs the microphone and says to the crowd: "I'm sorry I had to defeat an Australian. I'm sorry." Aaah.
1058: "Of course it's not easy but after today, I hope I'll have more crowd behind my back. Vera (Zvonareva) is a great player. We played many times last year and I just hope it's going to be a good match. Who deserves to win will win."
Semi-finalist Dinara Safina
1057: "Well done Safina, that cannot of been an easy atmosphere to play in with that very partisan Aussie crowd."
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1056: Safina is forced into another error to give Dokic two break points. The Russian finds her serve at the right time though, and when Dokic goes long, it's match point - with Rod Laver Arena stunned into silence. The Aussie slaps a tired forehand into the net and the dream is over. Safina goes through.
Result: Safina 6-4 4-6 6-4 Dokic
1049: Courageous stuff from Dokic. She saves one break point with a big serve out wide and then makes it deuce when she forces the mistake with some huge hitting. Safina uses up her last challenge by incorrectly going to HawkEye - but then reels off three points in a row to break again. She just has to serve it out now...
Latest: Safina 6-4 4-6 5-4 Dokic
1039: Dokic scoops the ball over and Safina gets the backhand all wrong, whacking it into the net. Break point... but Dokic goes wide. Deuce... but Safina goes wide. It is now that the umpire decides to give Safina an official warning for receiving coaching from the stands. Seems a little bit harsh. Dokic swings a backhand out wide to break back, prompting more deafening cheers from the crowd.
Latest: Safina 6-4 4-6 4-4 Dokic
1034: HawkEye is the crowd's new darling as Dokic challenges correctly again - and it wins her the game. Safina, with her unpredictable serve, will surely need a double break to seal this one.
Latest: Safina 6-4 4-6 4-3 Dokic
1031: Massive cheers on Rod Laver Arena as Dokic correctly challenges a call. Safina - her serve back on track for now - nails a wrong-footing backhand to make it 30-30 but Dokic produces a brave forehand, which lands right in the corner. Break point... but the Aussie is a little slow to a forehand and sees it fly into the trams. Safina clings on again. I imagine Federer and Del Potro - waiting in the locker room - are as gripped by this as we all are.
Latest: Safina 6-4 4-6 4-2 Dokic
1025: Dokic is in a bit of trouble at 15-30 on serve but comes right back. Apparently, she'll be back in the top 100 after this week regardless of what happens today.
Latest: Safina 6-4 4-6 3-2 Dokic
1023: "I was really happy to see Roger (Federer) win the US Open last year. If I'm being frank, he was a lot classier in that press conference than I would have been. He has nothing to prove. He's the greatest. He's created quite an animal for himself, where if someone wins a set they're questioning his form. The guy made two finals, a semi, and won a Slam last year and people are saying he's off form. I think he deserves a lot more respect than that."
Andy Roddick on Roger Federer
1021: By the way, if you find yourself with a bit of time on your hands, I recommend you head to the Aussie Open website and check out the transcript from Andy Roddick's press conference. Classy.
Latest: Safina 6-4 4-6 3-1 Dokic
1015: Dokic smacks a trademark double-hander crosscourt to save one game point and then Safina double-faults - FOR THE 11TH TIME. Dokic arrows a forehand down the line to make it break point, but nets a forehand. Few more deuces but Safina scrapes through the game, consolidating the break she earned in the opening game.
Latest: Safina 6-4 4-6 2-0 Dokic
1006: "I can't work out if it would be good or bad for women's tennis if Dokic went on to win the AO. On second thoughts, I'm way too premature with that question."
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1001: "That serve is an embarrassment. This match is not a great advert for women's tennis."
BBC analyst Sam Smith
1000: Safina has a point for 5-5 but slaps a forehand into the net. The Russian's serve has deserted her and after a double fault, she again slams her racquet down - prompting some pantomime "oohs" from the crowd. Another double fault gives Dokic the set. Someone asked earlier if Safina looked like she might choke. I think she just answered that herself. Goody. A third set.
Latest: Safina 6-4 4-6 Dokic
0957: "I think we should be doing more to talk this current quarter-final up as much as possible. It isn't THAT bad. It is arguably much better than the first ladies game today."
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0953: Safina holds quite comfortably to leave Dokic serving for the second set. But Safina breaks back. The Russian has won four of 15 break points in this match.
Latest: Safina 6-4 4-5 Dokic
0945: The noise inside Rod Laver Arena is by far the best thing about this match. Dokic breaks again, the highlight of the game a lovely off-forehand.
Latest: Safina 6-4 2-4 Dokic
0939: Safina break back. We've hit the half-century of unforced errors. Don't get me wrong, I love a bit of drama, but I am hoping this doesn't go to a third...
Latest: Safina 6-4 2-3 Dokic
0938: Here's Novak Djokovic talking about the possibility of being criticised for another retirement. "I did have some retirements, but I always retired with a reason. I don't see why should anybody, you know, take it or mean it that way. Whenever I retired, I retired because I felt I cannot go on. I mean, I don't... that's the only reason."
0933: Safina slams her racquet into the court Marat-style as a third break point slips by. Dokic somehow comes through the game but still neither player looks comfortable. The crowd don't care though. They are making a terrific noise.
Latest: Safina 6-4 0-3 Dokic
0926: "Re 0919: Some would argue it was an advantage to play at night because it was cooler."
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0924: Ropey old match this on Rod Laver Arena, neither player exactly shining - but we could yet witness drama. The crowd are again on their feet as Dokic breaks.
Latest: Safina 6-4 0-2 Dokic
0919: "Don't forget that due to the ridiculous scheduling, Djokovic didn't finish his last match until 2.30am on Monday. I think the organisers are to blame."
Anon via text on 81111
0917: If you're just waking up and wondering what that last comment was about. Novak Djokovic's title defence ended when he wilted in the heat and retired from his quarter-final against Andy Roddick. Roddick was leading 6-7 (3-7) 6-4 6-2 2-1 at the time. Would it have killed Djokovic to hang on for four more games? I don't think so. As Sam Smith says, it would have been "the classy thing to do".
0915: "Djokovic's preparation has been a bit of a shambles to be honest, and he paid the price today. That's in contrast to Andy Roddick, who looks like he's really benefitted from a good pre-season and looks like he can't wait to get on court."
BBC analyst Sam Smith
0913: Hmm. It turns out you would have been quite safe to count those chickens. Safina serves it out to love. Not sure Dokic has got enough in the tank to take this to three sets, but we'll see.
Latest: Safina 6-4 Dokic
0911: Safina, who is insisting on being called SAFina this year with the emphasis on the Saf, gets herself into the perfect position to put away the smash and gives it a loud "come on" as she breaks again. She'll serve for the set, but I wouldn't go counting any chickens.
Latest: Safina 5-4 Dokic
0905: "I can't believe how tight Safina is. She's not moving particularly well and she's sucking in air after every point which is a sign of how nervous she is. I thought she would come out and win this easily."
BBC analyst Sam Smith
0903: A double fault brings a disappointed sigh from the crowd, and gives Safina another break point. But Dokic sends up a perfect lob and Safina - who hasn't got the quickest wheels in the world - can't get back to deal with it. Dokic leads for the first time.
Latest: Safina 3-4 Dokic
0855: Nothing particularly complicated about Dokic's game: big, flat groundstrokes into the space. The Australian gets the crowd involved for the first time, pumping her fist as she earns three break-back points. Safina obliges with a backhand over the baseline and we're back on serve.
Latest: Safina 3-3 Dokic
0851: Already a few worried glances from Dokic to her boyfriend and coach in the stands. Very solid start from Safina here.
Latest: Safina 3-1 Dokic
0845: A huge roar greets Dokic as she gets herself on the scoreboard, but Safina still has the break. The winner of this match will face Vera Zvonareva in the semi-finals. She beat Marion Bartoli earlier, which means an all-Russian semi-final line-up remains a possibility.
Latest: Safina 2-1 Dokic
0840: Dokic's fitness could be a factor tonight. Not only is it ridiculously hot, but she hasn't played this many top-level matches for some time. Safina plays aggressively to break serve straight away.
Latest: Safina 1-0 Dokic
0837: Off we go then. Jelena Dokic to serve first. Sam Smith tells us this is going to be the hottest week in Melbourne for 100 years. Yikes.
0831: For the second day in a row, I find myself taking over this live text commentary shortly after the demise of a Brit. This time it's Jamie Murray bowing out of the mixed doubles with Liezel Huber. The older Murray is on a dreadful run of form and finds his Davis Cup place under threat. "It is not going to be the end of the world if I don't play," said Murray the other day. That's told John Lloyd then.
0828: Here come the players after the usual illuminating interviews in the tunnel. I think I can summarise by saying they're both very excited and hoping it's a great match. Me too.
0825: And that's all from me too folks - the sweltering heat here in Shepherds Bush has got to me and, just like Novak Djokovic, I am calling it quits. Over to Caroline Cheese to take you through today's remaining matches, starting with third seed Dinara Safina against a rejuvenated Jelena Dokic which is coming up in a matter of moments. Enjoy.
0819: Oh dear. It is all over on the Margaret Court Arena - like his brother Andy, Jamie Murray's bid for Australian Open glory is over as he and American partner Liezel Huber bow out of the mixed doubles - Nathalie Dechy and Andy Ram win the deciding super tie-break 10-4.
0806: Dechy and Ram hold out to take the second set 6-2 and level the match. If Murray and Huber do come through this one, they will face Dominika Cibulkova of Slovakia and Jurgen Melzer of Austria in the quarter-finals.
0755: It's not all plain sailing for Jamie and Liezel though. Far from it. They have been broken twice in the second set and Dechy and Ram are serving to go 5-1 up.
0740: I can't actually see any pictures of Murray and Huber in action on the Margaret Court Arena but that does not make their progress in the tie-break any less gripping. The fourth seeds have to save a set-point at 5-6 before eventually taking it 8-6. Marvellous.
"Joker risks being called a choker too (see 0648). He has done it in the past when things have not gone his way. It seems the conditions were dreadful but they seemed to have no effect on Roddick. Full credit to him, he served awesome."
VS from London via text on 81111
0729: I suppose it was all going too well...Dechy and Ram break back and we are into a tie-break in that one.
0727: And it gets better...Jamie Murray and his American partner Liezel Huber are serving for the first set in their mixed doubles second round match against Nathalie Dechy and Andy Ram.
0725: The Brits are still going strong too - Laura Robson and Heather Watson both won to reach the last 16 of the girls' singles.
0721: Here is a quick recap of today's action so far for anybody just waking up - Vera Zvonareva won 11 games in a row to crush Marion Bartoli and reach the last four of the women's tournament whilst Andy Roddick is into the semi-final at Melbourne Park for the fourth time after defending champion Novak Djokovic retired during their quarter-final.
0710: That Federer-Del Potro clash is the second floodlit match on the Rod Laver Arena. First up we have got another women's quarter-final with Dinara Safina up against Jelena Dokic. Both of those matches will be on the Red Button, this website and 5 Live sports extra from 0830 GMT.
0658: "All hail the Roddick diet!"
So says 5 Live's David Law after his earlier exchange with Jonathan Overend (see 0250). Law predicted an A-Rod victory while Overend went for Djoko - so is he eating humble pie now?
Oh, and by the way, Roddick will play the winner of the upcoming match between Roger Federer and Juan Martin del Potro in his semi-final.
0652: And does the spate of recent retirements at Melbourne Park tell its own story about the conditions the players are being forced to play under? The heat obviously played a big part in Djokovic's disintegration there...
0648: So, a dramatic end to Djokovic's reign as Australian Open champion. But should he have allowed Andy Roddick his moment of glory? Was he a bad sport for retiring early when on the brink of defeat, or was it the right decision for his health?
0643: "Djokovic had been feeling the heat for some time - he clearly needs to get out of the sun and get some medical attention. But Andy Roddick was playing in the same conditions and it was survival of the fittest - he still looked very fresh at the end."
BBC 5 Live's Jonathan Overend
0638: NOVAK DJOKOVIC RETIRES The defending champion calls it quits and Andy Roddick is through to the semi-finals. It's been coming...
Roddick 6-7 (3-7) 6-4 6-2 2-1 Djokovic
Ah, that could be that for Djoko. He is broken to love and, frankly, looks a broken man.
Roddick 6-7 (3-7) 6-4 6-2 1-1 Djokovic
No let up on the Roddick serve, however, as he thumps down some huge deliveries before hitting an inspired half-volley to hold with a flourish and put the pressure squarely back on Djoko's sagging shoulders.
Roddick 6-7 (3-7) 6-4 6-2 0-1 Djokovic
So, signs of life from Djoko at the start of the fourth set? Not really, more an opportunity missed for A-Rod. He lets four break-points come and go before the exhausted champion somehow produces a brilliant backhand to hold.
"Djokovic is clearly unwell in sweltering temperatures here. He is in real trouble so it was vital for him to hold in that game."
BBC 5 Live's Jonathan Overend
"Come on Roddick! About time A-Rod played this good in a Grand Slam - hope Djoko doesn't have to retire as this match is sizzling up nicely."
Anon via text on 81111
Roddick 6-7 (3-7) 6-4 6-2 Djokovic
Djoko has just had another visit from the doctor (the Djoctor?) but it does not help much here - four big serves by Roddick see him hold to love and he is now two sets to one up. The champion is looking pretty dejected at the moment, and he is on the brink of losing his title.
Roddick 6-7 (3-7) 6-4 5-2 Djokovic
Oh dear. A double-fault sees Djoko broken to love and Roddick is sitting pretty at the change-over - he is a double-break up and will serve for the third set next.
Roddick 6-7 (3-7) 6-4 4-2 Djokovic
Still, you should never write off a champion and Djoko is fighting on. He gets to 30-all thanks to some sharp returns but he needs every point to end quickly and A-Rod is having none of it. The American holds and Djokovic does not have much left in the tank.
0618: Djoko's eyes at the changeover told their own story - he is running on empty at the moment and he will have to dig very deep to get out of this particular hole.
Roddick 6-7 (3-7) 6-4 3-2 Djokovic
How tired in Djoko? Very tired. And he is in big trouble here too - Roddick, unsurprisingly, goes on the attack and he is rewarded by some sluggish shots by the Serb that leave him at 15-40. A-Rod is in at the net on the next point to win it with a delicious slice backhand and he is a break-up in this third set. Can the champion come back from this?
Roddick 6-7 (3-7) 6-4 2-2 Djokovic
All eyes on Djoko but, from this game, it is difficult to tell whether how much he is struggling at the moment because three double-faults from Roddick prove to be a bit of a distraction. A-Rod holds in the end though - now we will see how tired Djoko is.
0606: Let's remember that three matches on Monday ended prematurely thanks to injury or illness so just hope that Djokovic makes a full recovery and can continue properly here. We are about to find out too, as he is back out on court now - Roddick to serve.
0605: This is an official medical time-out for Djoko now. The trainer is rubbing down his calves and thighs although, looking at the Serb's face, I'd say he just needs a rest. Roddick is back on his feet, meanwhile, and strutting around the court.
0602: I'm not sure exactly what the problem is for the defending champion but he is not having any treatment as of yet. I'd wager heat exhaustion is a factor.
0600: Djoko is looking exhausted out there and things are not looking good - he has called out the trainer and a doctor at the changeover.
Roddick 6-7 (3-7) 6-4 1-2 Djokovic
Not sure quite why, or how, but suddenly both men are in real trouble on serve - a wild Djoko forehand flying wide to hand the American two more break points at 15-40. I suppose this makes up for the lack of chances in the first set-and-a-half. The rallies are still top quality, however, and, this time, Djoko steadies himself with some clever serving to get back to deuce before holding with a couple of killer forehands.
Roddick 6-7 (3-7) 6-4 1-1 Djokovic
Djokovic responds immediately but you can't help but feel for Roddick, as a lucky net-cord helps decide a thrilling rally at 30-40. Still, Djoko will not mind one bit - he has his first break of the match.
Roddick 6-7 (3-7) 6-4 1-0 Djokovic
Djoko's first two double-faults of the match are probably not the way he wanted to start the third set and, although he claws back to 30-all, things get worse when he plays a simply dreadful forehand to go 30-40 down. Can Roddick take advantage again? He can you know, as Djoko comes into the net but can only watch as a blistering forehand on the run from A-Rod zips past him down the line for a superb winner. Game on.
"Chris, where are you getting the 5 Live commentary quotes from? I can't find the match on 5 live sports extra or the red button?"
Phil in Watford, via text on 81111
My friends at Melbourne Park are giving us regular updates on BBC Radio 5 Live but we have no live coverage of this match I'm afraid Phil, apart from right here of course...
Roddick 6-7 (3-7) 6-4 Djokovic
That's the way to wrap up a set. Roddick starts with an ace, and three more big serves keep Djoko at bay and put the second set in the bag for the American.
Roddick 6-7 (3-7) 5-4 Djokovic
Roddick is on a roll and Djokovic is finding it tough to live with the pace he is putting on his shots at the moment. A-Rod has another chance to break when the Serb puts a crosscourt forehand wide but Djoko recovers to hold and stay alive in the set. That's the good news for the champion - the bad news is that he has got to break Roddick next.
"If Roddick continues to hit his forehand with the authority he has managed in this second set then he has a real chance of beating the champion here. Djokovic seems to be suffering in the sun a little at the moment."
BBC Sport commentator Chris Bailey
Roddick 6-7 (3-7) 5-3 Djokovic
Roddick needs a solid game here to press home his advantage...and that is exactly what he produces. He holds easily and is one game away from levelling this match at one set-all.
You cannot keep Laura Robson down at the moment - she is back out on court in the girls' doubles, pairing up with Anna Orlik of Belarus to beat Ester Goldfield and Hannah James 6-1 6-0 in the second round. Goldfield is from the United States but James is British so that's a Brit-down graphic too I'm afraid.
Roddick 6-7 (3-7) 4-3 Djokovic
Opportunity knocks again for Roddick at 30-all and, this time, a deep volley is good enough to bring him the first break-points of the match. The next point is a thriller too, with both players in at the net before A-Rod slams down an overhead - great stuff and the up-shot is that he has the break and has the lead in this second set.
Good news from the girls' singles, where Guernsey's Heather Watson has beaten Chanel Simmonds of South Africa 6-2 6-1 to join Laura Robson in the last 16.
Roddick 6-7 (3-7) 3-3 Djokovic
Roddick sent a racquet off to be restrung halfway through the first set, cryptically asking for it to be given to 'Roman'. It's still not come back and he had a little moan at the last change-over - not that it affects him much here, as a clever half-volley sees him hold easily.
Roddick 6-7 (3-7) 2-3 Djokovic
At last, a chance for Roddick at 0-30 on the Djoko serve. Can he take it? Well, no. A Djoko ace, a tame A-Rod forehand and another big serve take the Serb to 40-30 before Roddick sends a big backhand long. Chance gone - sorry folks...still no break-points in this one yet.
Roddick 6-7 (3-7) 2-2 Djokovic
Roddick, finally, manages his first forehand winner of the match to go 30-0 up, and follows that up with a sublime backhand slice to boot. Another forehand winner from A-Rod (he's showing off now) at 40-0 wraps up the game - to love, in case you were wondering...
Roddick 6-7 (3-7) 1-2 Djokovic
Um, not much subtlety about this match so far, and this game is no different. Djoko slams down four big serves, and Roddick gets something on a couple of them. not much, mind. The most exciting moment comes when Djoko, correctly, challenges a line call - and he holds to love.
Roddick 6-7 (3-7) 1-1 Djokovic
Wow. some huge serving from Roddick gets him off the mark in the second set. No danger of him wobbling here - he holds to love.
Roddick 6-7 (3-7) 0-1 Djokovic
Djokovic's fifth ace of the day takes him to 30-15 and some great defence by the Serb denies A-Rod his first baseline winner on the next point. At 40-15, A rare forehand error by Djoko gives Roddick another sniff but that is all he gets...and he has still not managed more than two points in a single Djoko service game.
0502: We are back under way...
0500: Both players have retreated off court at the end of that first set but I'm sure they will be back soon. In the meantime, here's an interesting stat - Roddick has hit 10 winners so far but none were with his forehand or backhand - he managed seven aces and three unreturnable volleys. Told you it was interesting...
"Djokovic's forehand is working brilliantly - it pummelled Andy Roddick in that tie-break."
BBC 5 Live's Jonathan Overend
Roddick 6-7 (3-7) Djokovic
Djoko gets a mini-break in the very first point and Roddick is suddenly so far back behind the baseline that he is lost in the shadows on Rod Laver Arena. A huge forehand presses home the Serb's advantage at 4-0 before A-Rod fights back but, at 5-3, the Serb gets a lucky net-cord for three set points. One crisp forehand into the corner later, and the champ has the first set in the bag.
Roddick 6-6 Djokovic
Two aces put Djoko in command at 40-15 but Roddick is still fighting and gets his reward when a Djoko forehand finds the net. A-Rod cannot return the Serb's next serve, however, so we are into a first-set tie-break.
Roddick 6-5 Djokovic
Ace number six takes Roddick to 30-0 and a crisp forehand brings him to 40-0 before a second double-fault of the match keeps Djoko alive. His next return is long, however, and the defending champion will serve to stay in the first set next.
Roddick 5-5 Djokovic
No trouble for Djoko on serve either. Do you spot a pattern emerging here?
"Nothing to choose between these two. We are more than likely heading for a tie-break where one mini-break could settle it. So a little bit of luck could decide the match."
BBC Sport commentator Chris Bailey
Roddick 5-4 Djokovic
Not many chinks in either player's armour after the early exchanges but Djoko is making more mistakes on his forehand and A-Rod does not seem to fancy his backhand too much. The defending champion is on the attack here, though, and gets to 30-all before a wild backhand is followed by a Roddick ace. The American holds again.
Roddick 4-4 Djokovic
I think they heard me too - a cracking exchange at 15-all ends with a whipped Djoko cross-court winner that wrong-foots Roddick all-ends up. Normal, erm, service is quickly resumed, however, as two more huge deliveries by the Serb see him hold and level the match again.
"Both men's first-serve success rate is very high at the moment - Roddick's is 85% and Djokovic's is 74% - which is not giving the returner much of a chance.
BBC Sport commentator Chris Bailey
Roddick 4-3 Djokovic
No stopping A-Rod either, who bangs down an ace to also hold to love. We did have one rally, in case you were wondering, which ended when Djoko put a backhand into the net. A few more would be nice...
Roddick 3-3 Djokovic
A blink-and-you-miss-it game by Djokovic, who holds to love. Both players have dropped just four points on serve so far.
Roddick 3-2 Djokovic
Djokovic's turn to reach a smash that Roddick should have buried but it matters little as that is the only point the Serb picks up. A solid hold for Roddick and no deuces yet in the first set - serves are dominating so far.
Both players have started very quickly and are hitting the ball beautifully from the back of the court. This one could go the distance but Roddick has got a real chance. It could be a brutal match, especially considering the conditions.
BBC Sport commentator Chris Bailey
Roddick 2-2 Djokovic
Not exactly convincing from Djokovic, who again finds himself at 30-all, but again he ups his game to hold. Roddick looks up for this one and almost fashions a break-point when he reaches a Djoko overhead. Not to be this time, though.
"Now that Andy Murray is out, I'm right behind the only remaining Scot, JOCK-O-VIC. I think his grandmother came from Dunoon. "
Anon via text on 81111
Roddick 2-1 Djokovic
Hmmm, I'm not sure how many service breaks we are going to see in this match. Not many, I'd wager. It is Djoko's turn to have a sniff at 30-all here before two huge serves from A-Rod quickly snuff out that sniff, so to speak.
"If Roddick wins this one I will bake him a delicious cake!"
Adam in Bath via text on 81111
Given his strict diet (see 0145 GMT), it will have to be some cake to tempt A-Rod.
Roddick 1-1 Djokovic
Not the greatest of starts on serve for Djoko, though, as two more unforced errors help Roddick get to 30-all. A delicate drop-shot puts the Serb back in control before a big serve sees him through.
Roddick 1-0 Djokovic
A straightforward enough start for Roddick, who holds without any fuss. Djoko makes the American work in a couple of rallies but wastes all his good work on both occasions with tame shots into the net.
0407: These two have got history you know. They had a bit of a run-in during the US Open last year when, ahead of their meeting in the quarter-finals, A-Rod - in jest - suggested that Djokovic always seems to be carrying an injury. Novak took offence, beat him in four sets, and complained loudly about the American's comments in his on-court interview afterwards. He was promptly booed by the Flushing Meadows crowd.
0404: Morning folks. So, A-Rod v Djoker? They are out on court and warming up - this should be tastier than one of Piers' sandwiches...
0402: With Roddick and Djokovic knocking up on the Rod Laver Arena I will pass you over to my colleague Chris Bevan, while I get on with numerous high-level tasks such as reports, pictures, quotes, making tea, staring blankly into space etc. Enjoy.
0400: We have some pre-match golden nuggets from the tunnel interrogation, first up Andy Rodick: "I've had good form so far but it's a new day and I just hope I can get through." And Novak Djokovic? "I've had a great tournament so far and hopefully I can continue." Great stuff.
0355: The Serbian fans are settling in on Rod Laver Arena, face paint very much to the fore, and Argentine legend Guillermo Vilas is among the VIPs. He hasn't had his face painted though.
0345: The Williams sisters are out on Margaret Court Arena and giving Peng Shuai and Hsieh Su-Wei the runaround - Venus and Serena lead 4-1.
0337: "I really played good tennis out there today, I had a lot of unforced errors in the beginning but then cut down on it and had a clear match," says Vera Zvonareva. "I'm looking forward to the semi-final, for sure."
And asked what she will do on her day off, the Russian says: "I'll probably relax, hit a little, watch a movie." Which is exactly what I plan to do on my day off. Minus the exercise.
0333: So next up is Andy Roddick v Novak Djokvoic on Rod Laver Arena at 0400 GMT. Over on Margaret Court Arena, women's doubles ninth seeds Daniela Hantuchova and Ai Sugiyama enjoyed an epic 6-7 (0-7) 6-3 7-6 (12-10) win over top seeds Cara Black & Liezel Huber. Hopefully, Huber will pick herself up in time to play in the mixed doubles with Jamie Murray later today.
0326: And there we have it - Vera Zvonareva beats Marion Bartoli 6-3 6-0 to reach her first Grand Slam semi-final. The Russian was playing well by the end but Bartoli suffered desperately in the heat.
0322: Nine games in a row now for Zvonareva. The order of play is out for Wednesday and we will kick off at 0000 GMT with Suarez Navarro v Dementieva, followed by Kuznetsova v Serena and Verdasco v Tsonga. The late/early match at 0830 GMT will be Nadal v Simon. Some of that will be live on the Red Button and 5 Live sports extra - details to follow later - but rest assured my colleagues Chris Bevan and Ollie Williams will be here all night on the text commentary.
0317: "To be fair," responds 5 Live's David Law in the BBC Tennis equivalent of Serena v Roddick... "Jonathan's two picks (see 0250) for the tournament are still in - Dementieva and Federer, so he is the form man at the moment. But then so was Andy Murray. Just been outside. The air temperature isn't that bad in the shade, but it's headache-inducing when you go out in the sun."
0314: Zvonareva rips through her own service game and looks set to take total command with break points in the next as Bartoli looks for the shade at the back of the court whenever possible - she's struggling. The Frenchwoman saves two but Zvonareva converts her third chance to lead 6-3 3-0. Eight games in a row for the Russian.
0303: Bartoli returns from her 'comfort break' with an ice pack around her shoulders and looking decidedly wobbly. She duly drops serve straight away at the start of the second set.
Elena Dementieva (right) is introduced to one of the locals
0258: Zvonareva wraps up the first set 6-3 with surprisingly little fuss and resumes the towel on head, ice pack around neck scenario while Bartoli heads off for a 'comfort break'. Meanwhile, Zvonareva's compatriot Elena Dementieva prepares for tomorrow's match against Carla Suarez Navarro by meeting a kangaroo. Nothing to add to that really.
0253: Zvonareva is the first to find anything approaching some form and, after Bartoli hits her fourth double-fault of the day, the Russian fires a beautiful backhand winner down the line for 15-40 and two break points. Zvonareva converts the second with another deep backhand and leads 5-3.
0250: "I reckon my colleague David Law is letting his lack of carbs affect his judgement in going for Roddick today (see 0145)," says 5 Live's Jonathan Overend. "He's also on the Roddick diet but still complains that housekeeping don't leave him any chocolates on his bed at night. His predictions this fortnight have been a load of fudge. I say Djokovic in four."
- You can feel the tension in the 5 Live commentary box from here.
0245: The bizarreness is back. Bartoli hammers what I think is a forehand well wide to give up another break and we're level at 3-3. The winner will play Jelena Dokic or Dinara Safina, both of whom must be fancying their chances.
0240: After the rather bizarre start to the match with three consecutive breaks, things have settled down on Rod Laver Arena and Bartoli leads Zvonareva 3-2 with a break.
0233: It has just occurred to me that backhands and forehands don't mean much when, like Bartoli, you play with two hands off both sides. Whatever, the Frenchwoman gets the third straight break of the match and the sometimes fragile - I think it's fair to say - Zvonareva heads straight for her chair and puts a towel over her head. Not exactly exuding confidence.
0230: "Just been into Laura Robson's press conference following her junior second-round win," says 5 Live's David Law. "There were about 15 or 20 of us in there - that's more than will come to the conference of the winner of the Bartoli/Zvonereva quarter-final. Apparently Serena Williams came up to talk to her recently. She said she felt a bit star-struck and speechless." We think he means Laura felt start-struck, but you never know.
0224: Zvonareva breaks straight back for 1-1 when Bartoli bunts a backhand both wide of the tram lines and over the baseline. And there's bad news for lovers of comedy tennis as Mansour Bahrami and Darren Cahill go down 7-5 7-5 to Wayne Arthurs and Pat Cash in the 'legends doubles'.
0219: It's not exactly bristling with energy on a largely empty Rod Laver Arena, maybe everyone is taking shelter from the relentless heat, but Bartoli is focused from the start and breaks Zvonareva at the first time of asking.
0211: "Roddick's diet won't win today's match for him. Djokovic could eat Big Macs for a year and still beat him."
From anon via text on 81111
0206: Finally, Bartoli and Zvonareva make their way onto the Rod Laver Arena, but not before the now customary pre-match 'interview' in the tunnel."I've been playing pretty well so I'm looking forward to this match," says Bartoli. "It's been a pretty good tournament and I'm looking forward to the match," counters Zvonareva.
Frost/Nixon it ain't.
0200: Today's headline in the Herald Sun: HEAT WAVE HELL
"Victoria is facing its worst heatwave in a century. The extreme heat starts today with a forecast of 38C followed by four days of 40C plus. Melbourne hasn't endured four straight days over 40C since 1908."
Andy Murray's better off out of there.
0157: Dellacqua-Schiavone fans, rejoice! They have raced through the final set 6-1 to see off Groenefeld and Schnyder, meaning the singles quarter-finals are about to kick off with Marion Bartoli against Vera Zvonareva.
0153: Day nine at the Australian Open should see the latest chapter in what is fast becoming tennis's greatest rivalry - Roddick v Serena. After Roddick has dealt with the trivial matter of his quarter-final against Djokovic he can get down to the real business in the press room. Having revealed that he lost a match to Serena when he was 10 years old, A-Rod said in mitigation that while he had been a skinny slip of a lad, Serena at the same age "could benchpress dump trucks". Not surprisingly, Serena responded yesterday, saying: "You know, he was a sweetheart. He was so sweet and he was so small. You know, he could never really beat me." Over to you, Andy...
0145: "Will Roddick's diet - no pasta, bread, potatoes, dairy or rice after midday - help him to reverse the result of the US Open when he plays Djokovic today?" asks 5 Live's David Law. "I reckon it will. He's the lightest he's been since he won the 2003 US Open, and moving really well."
0139: Top seed Noppawan Lertcheewakarn of Thailand beats Quirine Lemoine of the Netherlands 6-3 6-2 to reach the last 16 of the girls' singles and remain on course for a semi-final showdown with Britain's Laura Robson, who beat the Thai in last year's Wimbledon final.
0137: "What a tonic for breaking up with someone. Tennis comes to my rescue with the prospect of some good matches to ease the pain."
From Craig in Norfolk via text on 81111
0131: Great news for Dellacqua-Schiavone fans - they have levelled at one set all against Groenefeld and Schnyder. Hooray.
0128: Bartoli v Zvonareva is scheduled to start 'not before 0130 GMT' - and it won't. There is currently a women's doubles match in play on Rod Laver Arena, and it's heading for a second-set tie break. It looks blisteringly hot as usual but Patty Schnyder has still opted to wear a smock. Must be a Swiss thing.
0120: Jelena Dokic's estranged father Damir has been grabbing the headlines in Australia as he attempts to renew contact with his suddenly highly-successful daughter through the media. Damir brought his special magic to Wimbledon a few years ago and made quite an impression when he smashed a journalist's phone. But look out...
"I will speak to the British tennis federation and ask them to allow me to watch this year's Wimbledon and I hope they will respond positively because I am not under any sort of ban," says Damir.
"I am not a drunkard either and I will not go there to cause any problems, I just want to follow Jelena's progress."
Reminds me, must get a protective cover for my phone.
0115: Ten minutes queuing up to buy tea bags, all the while staring at a massive chocolate fudge cake, but I did not succumb. You can keep your Nadals and your Federers because that, my friends, is mental fortitude.
0112: "Ah waking up in the morning having Nicky Campbell telling you Murray was beaten. Talk about dampening spirits before a 9 o clock lecture! Oh well at least theres some cracking matches to come!"
From Kenny in York via text on 81111
0057: True enough, we are about to hit a bit of a lull before Bartoli v Zvonareva at 0130 GMT - never have I been so keen to watch Marion Bartoli - with the slightly more enticing prospect of Roddick v Djokovic at 0400 GMT. I am about to go in search of tea bags, but I will return....
0052: "piers this lack of action is almost enough to make me attempt to cram for my exam in 9 hours. disheartenin!"
From vicky in hants via txt on 81111
0052: "Is that the end of our Piers for the Oz open this year. If today is your last night."
From anon via text
- On the contrary, I am to be taken away and placed in a decompression chamber for several days before returning for the glory shifts of the semi-finals and final - which thankfully start in the mornings, if a bit early.
0049: "Well done Laura, keep the flag flying. I simply cannot wait for the Del Potro/Federer match. Roger is my hero!"
From Fabio in London via text on 81111
0048: So British legen... British teenager Laura Robson will play fellow 15-year-old Silvia Njiric of Croatia in the last 16. And we still have Heather Watson to come later in her second-round match. Andy who?
0042: "Still in deep post Andy trauma...at least young Robbo's still in there, go gal!"
From anon via text on 81111
0037: No messing. Laura Robson races through the tie-break and goes on to seal a 6-3 7-6 (7-0) victory and a place in the last 16 of the girls' singles. Come on Britain!
0030: A solid service game from Robson takes her into a tie-break with Narattana. I should also mention that Jamie Murray is in action later - he and Liezel Huber take on Nathalie Dechy and Andy Ram in the fourth match on Margaret Court Arena in the second round of the mixed doubles.
0025: She's back! Robson recovers the double break to level at 5-5. Never underestimate the power of Robbo. The winner here is likely to play Croatia's Silvia Njiric, who leads Russian Polina Rodionova 6-1 5-0.
0021: "Hey Piers, what you having in your sandwich tonight then?"
From Tony in London via text on 81111
- I have gone for the healthy option again as it's my last nightshift and have just realised I failed to bring tea bags - a double whammy.
0017: Well, Robson gets one of the breaks back and has now cut the deficit to 5-3 in the second set after winning the first. Ms Narattana is 16 years old and ranked, er, 941 by the WTA.
0016: "I'm in the south of spain trying to study for my spanish macroeconomics exam, whilst my polish and bulgarian flatmates dance loudly to reggae in the kitchen. Come on laura, give me something to smile about!"
From anon via text on 81111
0015: "Bit premature saying laura looked good for the next round wasnt it? C'mon!"
From anon via text
0012: Crikey.Narattanahas broken again and now leads 5-1 in the second set. It's a re-run of two days ago when I tipped Safina for the title after she won her first set against Cornet, and an hour later the Russian was facing two match points.
0007: "Evening Piers, doesn't Caroline Cheese have the best name in british journalism! Anyway im expecting A-Rod and R-Fed to go through. Enjoy the next few hours of tennis!"
From Tpott via text on 81111
0007: "Murray's reaction to the defeat was very positive, didnt dwell on it. Simply didnt take his chances. King Federer suffered a similar defeat at the same age in the same tournament. Good omen then..."
From Amrit in london via text
0007: "I don't think you understand how upset I really am that murry is out I really had faith that he was going to win. Oh how upsetting."
"From yvette, london, via text
- I do, I do....
0003: I say, Narattana has raced into a 3-0 lead over Laura Robson out on Court 21. I have no pictures but can only assume the Briton has been forced to play with her legs tied together, or something.
0001: "Thanks for the advice last night. Stayed up to watch the tennis despite my exam, as you suggested, and wasn't tired one bit. Here's to another night of tennis."
From Oli in Portsmouth via text on 81111
0001: "Piers...wat do u tink? Get some slp. Get up in time 4 fed's match.... Knowing safina n dokic, dats 3 hrs? Suggestions?"
From, alia, sheffield via text
-The sleep doctor is in. I think if you go to bed now and plan to wake up for Federer v Del Potro that should guarantee you at least 10 hours, which is nice. And I'd like to point out that I would never condone a carefree attitude to pre-exam rest and recuperation.
2358: So to day nine, and I have to say the main excitement looks to be some way off. The men's and women's quarter-finals kick off with Marion Bartoli against Vera Zvonareva at 0130 GMT, followed by Andy Roddick against Novak Djokovic at 0400 GMT. The late/early matches will be on the Red Button, this website and5 Live sports extra from 0830 GMT - firstly, Dinara Safina against Jelena Dokic, then Juan Martin del Potro against Roger Federer.
2350: Robson takes the first set 6-3 is looking good for a place in the last 16. Should she make the semis, the Brit is likely to meet top seed and arch-rvial Noppawan Lertcheewakarn of Thailand. Robson beat Lertcheewakarn in the Wimbledon junior final. I wish the future of British tennis had an arch-rival with a slightly shorter name.
2343: "Another day, another laura robson match. From what i gathered from yesterday's match, it was a rollercoaster. Today seems to be going the same. A female version of Henman maybe?"
From Johnny via text on 81111
-I think that might be a bitpremature. Yesterday's opponent was over a year older and 200 places higher in the rankings and was ultimately beaten in straight sets. Tim would have taken that when he was 15. Come to think of it...
2339: Narattana puts up some stern resistance early on and saves several break points before the damn breaks and Robson races into a 5-2 lead.
2330: I cannot deny there is an air of gloom surrounding our operation this evening and even the shouty bloke from Masterchef has failed to completely raise my spirits following Andy Murray's demise this morning. Having slept all day I've missed much of the reaction but I think my colleague Caroline Cheese sums it up pretty well. What a wise lady.
Murray defeat should not spell panic
2325: Robson is not the only British hopeful in the girls' singles and ninth seed Heather Watson takes on South African Chanel Simmonds later on Court Seven. What's this? Narattana has broken back against Robson. She's only making it worse for herself.
2320: I say 'little', but our Laura is now a lofty 5ft 10in tall and already looks like top-class athlete, despite having turned 15 less than a week ago. She had a real battle in her first-round match yesterday against American Christina McHale - ranked 374 in the seniors - but the Brit is already a break up at 2-0 on Narattana.
2315: Sometimes you wonder whether it's worth carrying on, but then it's not all about Andy Murray is it? The show must go on and who better to raise British spirits than little Laura Robson in the girls' singles? She is up against Thailand's Kanyapat Narattana in the second round on Court 21 right about now.