NEW YORK: Roger Federer was on a roll: new tactics, renewed confidence and 28 straight sets won coming into the US Open final.

But once again, Novak Djokovic was the antidote.

After stopping Federer in four sets in this year's Wimbledon final, Djokovic did the same on Sunday, prevailing against an inspired opponent and a hostile crowd in Arthur Ashe Stadium to underscore his status as the world's No. 1 player.

Djokovic's 6-4, 5-7, 6-4, 6-4 victory gave him a second US Open singles title and a 10th grand slam singles crown, moving him into a tie with Bill Tilden for seventh place on the career list.

Federer remains on top of that pecking order with 17, but Djokovic has prevented him from adding to his record total.

He is playing remarkable tennis at age 34, but Djokovic, at 28, is in his prime and remains one of the great tennis conundrums for any opponent with his tactical versatility and peerless defensive skills.

"A massive challenge," Federer conceded after his latest defeat.

Federer has fared much better against Djokovic than nearly anyone else, and their rivalry is the best the men's game has to offer at the moment with Rafael Nadal in a slump that could turn out to be decline.

Federer and Djokovic have played 42 times, and Djokovic's victory on Sunday tied the series 21-21. They have now played each other 14 times in grand slam tournaments, more than any other men in the Open era.

It remains a contrast in styles, even more so now that Federer has recommitted to the attack under his co-coach Stefan Edberg, the former Wimbledon and US Open champion who was a net-rushing marvel at his peak.

But Federer has yet to win a major title with Edberg in his camp, and Djokovic is hardly just a defender. He takes plenty of risks of his own and is particularly adept at transforming seeming vulnerability into offence when extended into the corners of the court.

The level of risk required to break him down is enormous, and he is also a moving target. The tactic that works in the first set may not work in the fourth.

"He's like a shark," Goran Ivanisevic, the former Wimbledon champion now coaching Marin Cilic, told BBC Radio here. "If he smells blood, he attacks."

Hardcourts have traditionally been his happiest hunting ground, suiting his precise footwork best. But US Open finals have been more stumbling blocks than showcases for Djokovic. He had lost four of the five in which he had played until Sunday. And he literally stumbled in the first set of this final when he lost his balance while changing direction in the fourth game and fell hard to the blue court, scraping his right forearm and looking a bit dazed for the next few points as Federer, who had been broken in the third game, succeeded in breaking back.

This much-anticipated final between the world's No. 1 and No. 2 players was delayed more than three hours by rain. When it finally did begin, it quickly became apparent (and audible) that Djokovic would be playing on the road, with the sellout crowd giving Federer nothing but positive reinforcement and greeting Djokovic's winners with polite applause at best and frequently cheering for his unforced errors and missed first serves.

Eva Asderaki-Moore, the first female chair umpire to work a US Open men's singles final, did her best to manage the partisan vibe. Her plea of "Please" became something approximating a mantra, and she also had a remarkable night reading the flow of play, making correct overrules and keeping a firm rein on a match that could easily have escaped control.

A lesser champion than Djokovic might have cracked in such an atmosphere, but this was hardly his first experience with Federer fever, hardly his first experience battling the crowd as well as the opponent.

He has played and won Davis Cup matches for Serbia for many years. He has beaten Lleyton Hewitt at the Australian Open, Jo-Wilfried Tsonga at the French Open and Andy Murray at Wimbledon, although he was the victim when Murray ended a 77-year singles drought for British men at the All England Club in 2013.

At this stage of his remarkable career, Federer plays in front of a home crowd in nearly every venue, a reality that has certainly made it easier for him to continue to find the motivation after having won all the major titles (except the Olympic gold medal in singles) that there are to win.

"It's definitely one of the reasons I keep playing," Federer said. "These goose-bump moments."

Djokovic was diplomatic enough to avoid any triumphant notes in his remarks during the awards ceremonies. If he is weary of playing against the Federer bandwagon, he did not mention it.

"I have a tremendous respect for Roger and what his game is presenting to me and to any other player," Djokovic said. "Coming out on the court and knowing you are playing against probably the best player in the history of the game definitely adds a bit more pressure, so you can always give your best, and I was trying to do so.

"Obviously stepping on the court and knowing he's going to be very aggressive and is never going to drop too much his level. He's always going to take the best out of you, and that was needed from my side to take this trophy. And it's quite an incredible evening for me."

Djokovic's victory made his season one of the finest in tennis history – even better in grand slam terms than his remarkable 2011 season, when he won three of the major singles titles and lost in the semi-finals of the French Open to Federer.

This year, he joined Federer and Rod Laver as the only men in the Open era to reach all four major finals, his only defeat coming in the final of the French Open against Stan Wawrinka, Federer's inspired Swiss compatriot.

Federer was clearly inspired himself on this summer hardcourt swing: winning in Mason, Ohio (beating Djokovic in the final), and then reaching the US Open final without losing so much as a set. But beating Djokovic over a best-of-five-set match is still the biggest challenge in men's tennis, and Federer, for all his tennis genius, has not managed it since the Wimbledon semi-finals in 2012.

"It was a tough night," Federer said. "But still thrilling."