Roger Federer proved once again that he still has a lot left in the tank. The No. 2-ranked Swiss Maestro defeated top-ranked Rafael Nadal 6-3, 3-6, 6-1 yesterday to win his fifth season-ending title at the ATP World Tour Finals in London. It was the first No. 1-2 ranked final at the year-end championships since 1986 when No. 1 Ivan Lendl defeated No. 2 Boris Becker at the Masters in New York. The 29-year-old Federer won back-to-back ATP World Tour finals in 2003-04 in Houston and 2006-07 in Shanghai. He also reached the final in 2005, finishing runner-up to David Nalbandian. Nadal has yet to win the year-ending finale. Federer, who had lost six of his last seven matches to Nadal, improved to 8-14 against his arch rival. The Swiss is now 3-0 versus Nadal indoors. Federer won an incredible 92 percent of his first service points and lost only 13 points on serve in the entire match. “I was able to stay offensive. Rallies were never that long,” said Federer. “That kind of maybe frustrated him.” Federer came out of the chute aggressively, hitting 14 winners to just just two for Nadal in the first set. The former world No. 1 broke Nadal at 3-4 with a cross-court backhand winner and then held at love to take the set. Federer became a bit tentative in the second set — perhaps thinking about his shots a little more rather than just hitting out. Nadal got the only break of the set at 1-2 and served it out to even things up at a set apiece. The turning point of the match came early in the third set, with Nadal serving at 1-2. Rafa took a 40-15 lead when Federer sent a return long, but the Swiss Maestro won the next four points to earn the break and essentially end a tiring Nadal’s chances of winning. Federer broke again at 1-4 and sealed the win on a looping forehand on the baseline at matchpoint. Never one to make excuses, Nadal squelched any notion that he was tired. Kind of. “Everybody saw the match of yesterday, so everybody’s free to think his own opinion,” Nadal said, referring to his 3-hour, 11-minute semifinal marathon against Andy Murray on Saturday. “I’m not going to say I lost the match because I was tired. What I’m going to say and what I feel is I lost the match because I played against a very good Roger Federer in one of his favorite surfaces. And when he’s playing like this, it’s very difficult to stop him, no?” The title was Federer’s fifth of the year, including his record-setting 16th Grand Slam championship at the Australian Open in January. “I know I didn’t spoil his vacation after this because he had an amazing year,” Federer said. “A year that any player dreams of.” Nadal, of course, won the French and U.S Opens, and Wimbledon.