US OPEN Venue: Flushing Meadows, New York Date: 31 August - 13 September BBC coverage: Live text commentaries on the website from 1600 BST each day, regular updates on 5 live, full commentary on 5 live sports extra in week two, both finals on 5 live. Live on Sky Sports and Eurosport.
Federer will face Djokovic for the third year running in New York
Defending champion Roger Federer withstood a superb fightback from Robin Soderling to win in four sets and reach the semi-finals of the US Open.
The world number one, going for a sixth straight title at Flushing Meadows, won 6-0 6-3 6-7 (6-8) 7-6 (8-6).
Federer will take on Novak Djokvic in his 22nd consecutive Grand Slam semi.
Fourth seed Djokovic survived a tough encounter with Fernando Verdasco to win 7-6 (7-2) 1-6 7-5 6-2 and reach his third straight US Open semi-final.
The final match of the day was a thriller, with Federer seemingly on course for a regulation win after playing some supreme tennis for two sets, only to see Soderling battle his way back into contention.
Federer had won all 11 of their previous meetings, including straight-set wins in the French Open final and at Wimbledon this year, and he began magnificently.
"It was so close towards the end and it's just a great relief to come through
Untouchable on serve and faultless off the ground, the Swiss took the first set in 25 minutes and had dropped just three games by the time he went two sets clear inside an hour.
Soderling had not been playing badly but he simply could not live with the top seed until the third set, at which point his own serve began to keep Federer at bay.
The Swede battled to a tie-break but was in big trouble at 5-2 down, only to reel off four straight points on his way to taking the set.
And as the fourth set progressed in similar fashion there was a growing sense that Soderling could force a fifth and threaten a spectacular upset.
Another tie-break was required and there was nothing to choose between them until Soderling played a poor return on set point at 6-5, and then fired a forehand wide on Federer's first match point moments later.
"This feels great," Federer said. "It was so close towards the end and it's just a great relief to come through because Robin just got better and better as the match went on.
"I knew it was going to be tough but the beginning was a bit too easy and all of a sudden he found his way into the match and showed what a great player he really is."
And on extending his own record of consecutive Grand Slam semi-finals to 22, he added: "It's not a record I aimed for, that's for sure, but it's probably one of the greatest records for me in my personal career.
"I'm just happy it keeps on going. I'm healthy and I guess that's most important because that's what has allowed me to play well at majors and I'm in for a shot again to defend my title so that's fantastic."
Earlier in the day,Djokovic saved two set points before taking the opener in a tie-break but Verdasco stormed back to level before being edged out of the third, and he was then hampered by injury as Djokovic sealed victory.
Federer has ended Djokovic's hopes of success at Flushing Meadows in each of the last two years, beating the 22-year-old Serb in the final in 2007 and in the last four 12 months ago.
And Djokovic will know he needs to produce a more consistent performance than he did against Verdasco if he is to reach Sunday's final.
"First set, the quality of the match wasn't its best," said Djokovic. "I've made a lot of unforced errors, he's made a lot of unforced errors, and I was lucky to get through in the tie-break
"I just tried to focus myself in the third set and work on some things. I returned more balls in on his serves, and I think serving well was as well one of the key elements in today's win."
Verdasco's thumping forehand gave Djokovic plenty of problems and, had he not been affected by an abdominal injury in the latter stages of the match, the 10th seed might not have faded so badly.
Djokovic was let down by his forehand in the first set and needed two big serves to save two set points at 4-5 before finally finding some fluency in the tie-break.
The thing today was that I had Djokovic in front of me, and he's a great player, very good player, one of the best
Verdasco came back brilliantly, reproducing the form he showed to reach the last four at the Australian Open in January and hitting some huge winners to break three times and run away with the second set.
The world number four was rocking and looked in serious trouble when he faced another break point at the start of the third set but, for once, Verdasco did not go on the attack and the chance was gone.
Both players continued to go for their shots as the match wore on but it was Djokovic who struck at the right time, breaking at 5-5 and serving out for the set.
Verdasco fought on, saving three break points at the start of the fourth set, but he was soon calling for the trainer after aggravating an old injury and looked in pain as he lost the next four games, and with them any hope of victory.
"I think that the problem was there, and everybody knows about it," the Spaniard said afterwards.
"The thing today was that I had Djokovic in front of me, and he's a great player, very good player, one of the best."
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