London:
Nikolay Davydenko clinched the last semi-final berth at the ATP World Tour Finals as the Russian defeated Robin Soderling 7-6 (7/4), 4-6, 6-3.
Before the day's play began, Davydenko knew a victory over Soderling would be enough to guarantee his place in the last four at London's O2 Arena on Friday.
Novak Djokovic's win against Rafael Nadal earlier on Friday kept the pressure on, but the Russian's fate remained firmly in his own hands.
He completed the job with a battling display in a match of the highest quality to ensure he qualified from Group B at the expense of Djokovic, who had beaten him in last year's final.
Davydenko finishes second in the group and will face Roger Federer in Saturday's opening semi-final, while Soderling takes on US Open champion Juan Martin Del Potro in the other semi.
Now Davydenko has only a matter of hours to recover from playing Soderling before he has go up against Federer and the Russian is unhappy with the ATP's scheduling.
"I have no time (to recover). It's a mistake from the ATP because these guys doing the times for the semi-final know what time we need to play," Davydenko said.
"I play the night session and then the next day at 1400GMT. It is a mistake by the ATP. It's obviously there. It's not my mistake but I hope I be fit."
Soderling added: "It's a great feeling (to be in the last four). It gives me a lot of confidence beating Nadal and Djokovic. I lost in a close match to Davydenko, which with a little bit of luck I could have won.
"It's going to be a tough match against Del Potro that's for sure. He plays really well. He serves big. He's hitting his forehand very well and plays fast.
"So I think I have to play very well to have a chance. For sure I have to play better than against Davydenko."
Soderling is only competing in this season finale because of an injury to Andy Roddick, but his victories over Djokovic and Rafael Nadal had made clear his determination to take advantage of his good fortune.
The 25-year-old is the first Swede to reach the semi-finals of the event since Jonas Bjorkman in 1997 and he is set to rise to eighth in the world as a result of his performances here.
But Davydenko had recovered from his opening match defeat to Djokovic by crushing Nadal in straight sets on Wednesday. The Russian earned his first break point in the seventh game but Soderling closed the door on that opportunity with a powerful serve.
Soderling, who had won six of their previous nine meetings, failed to convert two break points of his own in the next game and the set went to a tie-break.
At 4-4 in the breaker, Soderling tamely netted to hand Davydenko the chance he had been waiting for. He needed to win both service points for the set and did just that, finishing the job with an emphatic smash.
Soderling had to save a break point at 2-3 in the second set and had another scare when falling awkwardly while hitting a forehand two games later.
He showed no signs of any damage, however, as he broke Davydenko to love for a 5-4 lead before serving out the set.
Davydenko refused to be discouraged by that setback and broke for a 4-2 lead in the deciding set.
That was enough to end Soderling's resistance as Davydenko held serve twice to go through.