Roger Federer became the first man in the Open era to win four consecutive US Open titles with a straight-sets victory over Novak Djokovic.

For once, the Swiss maestro did not produce a true masterclass, but he prevailed 7-6 (7/4) 7-6 (7/2) 6-4 at Flushing Meadows.

The key to his victory was simple - playing the big points the better.

In both of the opening two sets Federer had to save set points but he stood firm while Djokovic felt the pressure of playing in first Grand Slam final.

In the first set the Serb was unable to serve out at 6-5, missing five set points before double faulting to hand the break of serve back.

Federer made him pay in the tie-break, coming from a mini-break down to take it by seven points to four.

Djokovic responded well to that disappointment, racing into a 4-1 second-set lead but again he squandered his advantage as Federer hit back to level at 4-4.

However, the Serb still managed to bring up set points - this time with Federer serving at 5-6.

An ace from Federer followed by a Djokovic forehand which went inches long saw both opportunities pass by and again the third seed was left to regret his missed chance.

Federer played a near-perfect tie-break, producing four first serves as he took it 7-2.

Dressed all in black, a la Mike Tyson, many thought that would be the knockout blow but Djokovic dug deep to fight back, but again couldn't take his chance.

In the fifth game of the third set he missed three break points - on one of them he bizarrely misjudged a Federer shot, leaving it and seeing it drop in court.

That was to prove the last chance for the 20-year-old.

Federer saved some of his best for last, breaking with some breathtaking play in game 10, the match ending with a tame backhand into the net from Djokovic.

Federer collapsed to the court in delight before returning to his feet to celebrate a 12th Grand Slam title.

Only Pete Sampras now stands above him on the all-time list and he will surely be toppled, possibly here in New York in 12 months' time.

The Swiss was generous in victory, saying: "I think straight sets is a bit brutal for Novak to be honest.

"He deserved better than that but he had a fantastic run, not just at this tournament but the entire year.

"So congratulations, keep it up, he's going to have many more battles I think."

Federer admitted he had felt some pressure over attempting to win his 12th grand slam.

"I've had an upset stomach the last few days, nervous, shaking, cold hands before the match, I've had it all. I'm supposed to be the experienced guy who has got used to the situation but you never do get used to it.

"But it's too nice to be true to be back in a grand slam final, I've really enjoyed tonight and the last two weeks and I'm looking forward to be back next year."

Meanwhile, Djokovic paid tribute to his conqueror, who picked up US$2.4million for his win, a total which includes a bonus of $1million for winning the US Open Series in the run-up to the event.

"He showed that he's the best. He deserved to win today - he was the better player."