The victory was worth $2.4 million to the Swiss world number one, but the only figure Federer really cared about was moving his grand slam titles haul to 12 to tie Roy Emerson for second place on the all-time list, two behind Sampras.

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"I think about it a lot now, honestly," Federer, 26, told reporters when asked about his quest to reign as the most successful grand slam winner in tennis.

"In the beginning I felt pushed a little bit in the corner, because you don't win slams (just) like that. It's just too tough.

"I feel these two and a half weeks, it's so draining. I'm exhausted in the end.

"I know how tough it is. So to come so close already at my age is fantastic, and I really hope to break it."

Federer, who became the first man since Bill Tilden in the 1920s to win four U.S. titles in a row, has also won five Wimbledons in a row -- the only man to possess such a streak in the final two grand slams of the year.

"BEST FEELING"

Despite all his grand slam experience, Federer said he still gets nervous before the big matches.

"You're like, 'I hope I didn't come all this way to lose'. You start asking yourself questions. Of course, the more I win the more I ask myself questions. In the end to win, it's relief, happiness, just all together. It's the best feeling."

The Swiss master said his greatest advantage is his mental toughness and how he can raise his game on the big points.

Federer said his game has changed a lot since he was an up-and-coming 20-year-old like Djokovic.

"I would chip and charge, serve and volley a little bit, play like my idols basically -- Becker, Edberg, Sampras. They all did it, so for me it was like I got to play the same way.

"Then I realised things were slowing down. The new string generation came along where returning and passing shots was made easier. It was harder to attack in some ways.

"But at the same time that helped me now because I do have the game to attack, I do have the solid volleys, I do have the opportunities and the option if I have to. That's good that I did it when I was young. I took some chances.

"Maybe that cost me a lot of matches, but the reward was fantastic. It's been a long road. I had to work hard on my game. In the end, I think I've really come along in the last few years."

In the last two years, Spain's Rafael Nadal [Images] has been Federer's chief rival, beating him in the finals of the last two French Opens -- the only slam that has so far eluded him.

Federer said Djokovic, who defeated the Swiss in this year's Montreal final after beating Andy Roddick [Images] and Nadal on the way, might join Nadal as a challenger to his supremacy.

"It's very possible, you know. Honestly I've enjoyed the challenge of young guys challenging me. This is probably my biggest motivation out there.

"You know, seeing them challenge me, beating them in the final, it's really for me the best feeling, to be honest," Federer said with a smile.

"If a rivalry comes along, great."

Federer said he was unsure how close world number three Djokovic was to overtaking Nadal as number two.

"Number two, number three, doesn't matter much," said Federer. "It's number one that matters. That's how it goes."

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