London - Roger Federer earned a three-set victory over Rafael Nadal to capture the championship at the ATP World Tour Finals.
Federer posted a 6-3, 3-6, 6-1 triumph on Sunday to claim the season-ending tournament for the fifth time in his career. He notched his fifth title of 2010 and the 66th of his career.
Nadal, who captured three of the year's four Grand Slam events and will still hold the No. 1 ranking, has never won this title. He won seven tournaments in 2010, including the French Open, Wimbledon and U.S. Open. Federer won the Australian Open.
After the two split the first two sets, each breaking the other's serve once, Federer had the first opportunity to break in the third set when Nadal sent a forehand wide in the fourth game. Federer then took advantage of a second serve to race the net and Nadal drove a forehand pass wide to give the Swiss star a 3-1 lead.
Federer then held serve and gained two break points in the next game. He needed just one to grab a commanding 5-1 lead after Nadal netted a backhand. Federer then opened a 40-0 lead in the final game before Nadal won a point, but Federer sent a forehand winner into the corner to finish the match.
"Even though I lost the second set, I'm really happy the way I stayed positive throughout the match today," Federer said. "I thought it was clearly a very high level. I don't know if I could have played any better, so I'm really pleased."
In addition to his Australian Open crown in January, Federer also won titles at the Cincinnati Masters, Stockholm and Basel. After a loss to Novak Djokovic in the U.S. Open semifinals, his match record was 21-2 to close the season.
Federer went 5-0 this week, including a perfect record in round-robin play and a 6-1, 6-4 dismantling of Djokovic in Saturday's semifinals. He didn't drop a set until Sunday's match.
Nadal, meanwhile, had the tougher road this week. He was also unbeaten in the round-robin portion, then played for three hours on Saturday in a three-set thriller against crowd favorite Andy Murray in the semifinals.
The quick turnaround may have played a factor for Nadal, who appeared to run out of gas in the third set.
"He played unbelievable," said Nadal. "He was unplayable I think in this first set. I just can congratulate him for his victory and another great tournament for him. He played unbelievable during all the week without losing a set [until] the final. So his level was very high. I tried my best this afternoon, but he was better than me."
Federer gained the first break of serve for a 5-3 lead in the opening set with a cross-court backhand and went on to hold at love, capturing the set with a forehand winner. Nadal turned the tables in the fourth game of the second set with two break points. He failed to convert the first, but a Federer forehand went long on the second to give the Spaniard a 3-1 lead and he held the rest of the way to force a decisive third.
A dominant serve helped Federer on Sunday, as he blistered seven aces to just one for Nadal and won 37 of his 40 first-serve points.
Sunday marked the first time the two top players in the world reached the final at the season-ending event since a top-ranked Ivan Lendl beat No. 2 Boris Becker in 1986.
The victory for Federer on Sunday was just his second in the last eight meetings. Nadal won this year's only previous matchup, claiming a 6-4, 7-6 (7-5) triumph in the Madrid final back in May.
Federer has now won four of the seven meetings on hard courts between the two, but Nadal still leads the all-time rivalry, 14-8. Nadal also still owns a record of 12-6 against Federer in title matches.
In Sunday's doubles final, Daniel Nestor and Nenad Zimonjic notched a 7-6 (8-6), 6-4 win over the duo of Mahesh Bhupathi and Max Mirnyi. It was the seventh title of the year for Nestor and Zimonjic, who knocked off the No. 1 ranked Bryan brothers in the semifinals and will play with new partners in 2011 after a three-year run.