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ALL THE ACTION (all times BST)
BBC Sport's Tom Fordyce in Berlin:
" Draw for the 100m semis just been made: Bolt v Bailey v Tyrone Edgar in the first; Gay v Dwain v Asafa P in the second. Smell the speed."
OK, day over. After a slow start that bubbled up nicely with some cracking drama. Go get some sleep Jess. She's buzzing though and has nine fingers already on that gold. What's up on Sunday then? Women's 800m at 0910, Ennis is in the long jump from 1035, her javelin's at 1705 and the dreaded 800m is at 1950. Triple jumper Phillips Idowu begins, Christine Ohuruogu goes in the 400m semis, and of course it's the men's 100m semis and final. Exciting times. Video starts at 0900 and then join me with the live text again later in the afternoon. Thanks for all your comments. I'm off to brush up on my shot put with one of the BBC's finest jacket potatoes.
Action winding up now and Kate Dennison's made the pole vault final. Cracking effort. She says: "I'm really happy. I wasn't jumping amazingly. First job done and it's all about the final."Pole vault looks a mad event. Looks fun though. I'd be worried about getting stuck on that bar.
From anon. via text on 81111:
"Usain bolt would dance all the way to victory! who wouldn't want to see him strut his stuff?"
Anything you can do I can do better. GB's Louise Hazel storms ahead to win her 200m heat with Nataliya Dobrynska having a nightmare. Watching Ennis lap up all the interviews must have felt like a big slap in the face for the Olympic champion.
American Christian Cantwell is world shot put champion. He's a big man and he's stomping round the arena, clapping his hands, and looks pumped up like a bull parading in a show arena. Brilliant. He wins with a throw of 22.02m. Poland's Olympic champion Tomasz Majewski is second ahead of German Ralf Bartels.
Ennis's coach Toni Minichiello:
"I'm chuffed to bits. It's so different to last year after she'd broken her leg. She takes it in her stride. Being world number one means nothing. It's all about delivering the performances. The shot put was fantastic. It's only half-time. It's nice, bit of history and there's still a championship to win."
After racking up the third highest ever score after day one in the heptathlon, Ennis says: "I can't believe it. That's mad - that's the the best day and the best start and I just hope I can continue it. I was just thinking before the 200m 'don't mess up!' It's looking good but I don't want to get carried away. I just need to get those last three events right."
Denise Lewis on Jess Ennis:
"Jessica has been outstanding. She's come here not to just win but to win it emphatically. She's so powerful and it's such a highlight to end the day with such a big score. She's put some very good athletes behind her."
Ennis adjusts her hair, clinches her fist and they all have to get up because one of the girls is ahead of the line. C'mon. Nervy times. 'On your marks'.....(seems like an age before the next word)...'set'....and it's a false-start.....yeh thanks for that. And they're off. She's flying and she wins in 23.25s. Not a PB but that's the conclusion of a cracking day for her.
Jess Ennis is in the first 200m heat. She's wearing a bib that reads 'Leading', which is weird. Deep breaths for the Sheffield lass. She paces round the blocks nervously, waves to the crowd in lane 7. She steps into the blocks and waits....
Britain's Kate Dennison clears 4.55m with her first attempt. That could be enough to make the final.
Jess Ennis's coach Toni Minichiello on her tactics for the 200m:
"She's going to tonk it."
From anon. via text on 81111:
"Why doesn't Michael Johnson do Strictly Come Dancing? I will vote for him. Steve Backley too."Good shout. Which athlete - ex or current - do you think would be the best dancer?
It's 15 minutes to go before heptathlete Jess Ennis goes in her day's fourth event - the 200m. It's 11 hours since she started in the hurdles. She's got to be feeling super-confident.
1951: Michael Johnson on David Greene's win:
"David came in and produced the time when he needed to. That's got to give him huge confidence for the semi-final."
Hold on. That wasn't supposed to happen. David Greene. Double Olympic champion and the fastest man in the world in the 400m hurdles is beaten by the Swansea star. He looked comfortable, so relaxed and keeps pushing until the final 15 metres and then eases off with all the runners nowhere to be seen. Stunning. "Quite a smooth run," he says.
Britain's Carl Myerscough fouls his last throw and is out of the shot put. Shame. David Greene next in the 400m hurdles.
American Kerron Clement clocks 48.39 with a tremendous showing in the hurdles. Danny McFarlane also comes through along with Trinidad's 17-year-old Jehue Gordon. Felix Sánchez disappoints in fourth. Clement says: "It's all about being confident and winning races and that's what happened."
Puerto Rico's Javier Culson wins the next 400m hurdles heat and American Bershawn Jackson puts in a storming finish for second spot. Rhys Williams struggles in the outside lane and ends strongly but it's only fifth place. Probably not enough though.
Britain's Carl Myerscough fails to make 20m in the shot put. His beard is wobbling with frustration. Rhys Williams up next in the 400m hurdles.
First heat of the men's 400m hurdles. Jamaican Isa Phillips cruises round in 49 seconds and what else would you expect from a man wearing green and yellow sunglasses? American Johnny Dutch - my favourite name in Berlin so far (surely a character in Guy Ritchie's next film) - also qualifies.
First up with a medal on the podium. Olympic champion Valeriy Borchin of Russia looks a happy chappy as his neck now proudly shows off his world gold medal after winning the 20km walk earlier on Saturday.
From lsabre on 606:
"Dwain Chambers has looked very good and composed all the way so far, he could snatch a medal on this sort of form!"
From FranMerida on 606:
"epic fail from Defar."Epic? Bit harsh but her legs turned to jelly at the end there. And as for Melkamu who celebrated over the line before turning round to see she had been pipped. Her face turned to stone.
That was an astonishing finish. Ethiopia's Meseret Defar looked certain for gold. She led with 30 metres to go. Meselech Melkamu then took over. And then Linet Chepkwemoi Masai grits her teeth and comes from nowhere to win. Unbelievable. All quiet for 15 minutes and then boom. Great sprint finish.
Three laps to go with Grace Kwamboka Momanyi, Masai and Ethiopian Meseret Defar streaking ahead.
The pace is cranking up. 76 second laps are down to just under 70 now. Masai leads a small pack of five runners including three Kenyans.
Kenyan Linet Chepkwemoi Masai has been taking it easy at the back of the field but she cruises up to the front. The field is opening up now. Elvan Abeylegesse limps out of the race.
Commentators Brendan Foster and Steve Cram are asking "when is anything going to happen in this race?" Konovalova still leads, but hold on. She's looking at that sticker. If I was running behind her I'd try to step on it. That would be well worth a medal.
From shivfan on 606:
"Bolt will win. This is the second time Gay has started badly, and had to work hard to win it. This is bound to have an effect on him tomorrow"
BBC's Steve Cram has also spotted the sticker. He reckons it would only take one second to bend down and take it off. Could be the greatest athletics debate ever. Maybe.
Russian Mariya Konovalova is stretching the field and leads in the 10,000m but she's suffering from something that happened to me last week when I went out shopping. She's got a massive white sticker stuck to her left shoe and it's flapping about like a big wet fish. Don't think she'll stop for a couple of minutes and peel it off like I had to. Only 17 laps to go. Who'd be a long distance runner eh?...
It's the first track medal up for grabs with the women's 10,000m final. The man with the starting gun looks like he's struggling to find the trigger. All good though eventually. We're off....
Usain Bolt on BBC Two:
"I was happy I got out so I didn't need to do anymore work. I was just enjoying myself."
From knowledge_is_good on 606:
"Can Bolt please take it seriously? That was too easy, we'll be watching a coronation tomorrow unless Gay sorts his start out, or Powell somehow manages his nerves."
Three blinks and it's over. Not that I did blink. Oh my lordy. Bolt and Bailey actually end up running those last 15 metres smiling at each other. I thought they were chatting then. Massive grins. Bailey clocks 10.02 with Bolt 0.01s behind. Williamson in fifth looked like he was running in concrete slippers.
Guess who's next up?....boy Bolt is back. And Briton Simeon Williamson is up against the Jamaican and Bolt's training partner Daniel Bailey. Let's see shall we.......
These boys are winding it up. Tyson Gay puffs those cheeks out, eyes as big as saucers and clocks 9.98 ahead of Michael Frater. The American had to work quite hard for that.
Asafa Powell is looking fired up in his 100m heat after his earlier mess-up in the first round. And Powell breaks the 10 seconds. Whooooosh. He clocks 9.95m and that's after slowing down in the final 20 metres.
"I scared myself. I was really panicking but I knew what I needed to do and got it together in the final round. It's been a brilliant day, everything's gone so well so I want to rest a bit then run a stormer in the 200m."
Michael Johnson on Dwain Chambers
"He's really patient here and this is what's important about Dwain Chambers' experience. he's running a really solid race. If he continues with this style of running he will be very successful in the final. I didn't think he would be a potential medallist but that bronze medal is still wide open."
Ennis now leads Nataliya Dobrynska in the heptathlon by 138 points. The 200m comes up a bit later. She's bubbling over trackside. Smiles all round.
Disqualification in the 100m for France's Christophe Lemaitre for a false-start. Heads in hands. Can't be nice. American champion Michael Rodgers wins easily in 10.01 and Tyrone Edgar puts in a stunning finish to grab second spot clocking 10.12. Top effort.
BBC Sport's Tom Fordyce in Berlin:
"What an effort from Jess Ennis - 14.14m in the shot put, a big personal best just as Nataliya Dobrynska looked to be closing that overall lead. It's been lost on the crowd as the heats of the 100m get underway, but that's big, big news for the number one British hope."
Dwain Chambers on BBC Two:
"I am very pleased. I felt great this morning. As you get older it takes longer to recover. It's going well and I'm looking forward to tomorrow."
First up is Dwain Chambers and he is flying. It's a season's best 10.04 and beats Olympic silver medallist Richard Thompson in that first 100m second round.
Ennis struggles with her second shot put throw. Doesn't even make 13m. Dobrynska is dominating in this event and her overall placing moves from sixth to second. 100m heats in two minutes.
Brit James Brewer cranks his legs up and in his first major championships comes through in the 1500m heat in third spot with a personal best. Magical effort. Could be bad news for Tom Lancashire though.
From Englandman on 606:
"Don't get excited about Ennis yet. She should be leading the heptathlon, as she's done two of her best events. The key is for her to get close to her PB on the shot and javelin, so she doesn't lose ground."
Jess Ennis winds that arm up and gets going in the shot put. Olympic champion Nataliya Dobrynska is looking solid and could be breathing down the neck of the Brit after this event. Ennis chucks in a throw just over 13m. Not a disastrous opener.
Andy Baddeley cruises into the next round in the 1500m with a great late burst and makes fourth. More elbow-battering but Baddeley keeps out of trouble.
BBC Sport's Tom Fordyce in Berlin:
"Probably only a third full at the Olympiastadion this evening, but the punters are making a decent racket between munching on currywurst and beer. Alcohol-free beer, it should be said. We're not in Hamburg, after all. All British eyes on Jess Ennis in the shot put, one of her weaker events."
The second heat of the 1500m is full of drama. I haven't seen such pushing and shoving since a fight I saw between two girls in Salisbury market place a couple of months ago. One of the runners ends up on the grass, runs for 20 metres and heads back on the track. Amazing. Lancashire was in a good position but struggles towards the end and clocks 3:42.68 way back.
Quick timetable round-up. Heptathlon shot put 1720. 100m heats from 1750. Women's pole vault from 1800. 10,000m final at 1825. Men's shot put final at 1915. Men's 400m hurdles at 1920. The night finishes with the heptathlon 200m. Keep your thoughts coming in.
First heat of the 1500m is the night's first action. France's Mehdi Baala looking useful and smooth and wins. GB's Tom Lancashire next up. Bernard Legat is in this one as well.
Michael Johnson on BBC Two:
"When you contrast Tyson Gay's heat with Usain Bolt's it is worrying for the American. He had to put in a lot of effort just to get through to the quarter-final."
Jess Ennis on BBC Two:
"I'm a bit disappointed with my hurdles as I wanted to win quicker than that. But I'm pleased with the high jump though and I felt really good out there. It was nice to start with two of my strongest events, I'm feeling good and looking forward to the rest of the day."
The video is up and running - on the website and BBC Two. It's 50 minutes and counting before the 100m second round gets going. The flags are flapping in the opening ceremony. BBC presenter Hazel Irvine assures us the ceremony will only last for half an hour.
From Nitebot9 on 606:
"Ennis looks in great form and it's hard to see her not winning. Gay looks injured. I can see him pulling up before the final. Chambers will make the 100m final but Williamson probably won't."
So what might have you missed so far? Olympic champ Usain Bolt and reigning world champion Tyson Gay cruised through their 100m heat. Asafa Powell had a lucky escape after slowing down half-way through his heat. As for the Brits, Dwain Chambers clocked 10.18 - second fastest of the morning, while Simeon Williamson and Tyrone Edgar are also through.
In case you want to keep across the football as well, then join BBC Sport's Chris Bevan who's describing all the action on
the live football text.
Just make sure you come back.
Who said it's too early for the football season? I did, that's who. It's all about the World Championships. It's athletics. It's in Berlin. Right here, right now. Day one. The fastest boys on the planet go in the 100m second round at 1650 BST. GB's Jess Ennis gets stuck into the shot put after a fine morning. She leads the heptathlon. Before that it's the crazy world of the opening ceremony. Bring on the 10 foot inflatables. All thoughts, predictions and general randomness welcome via text or 606.