NEW YORK - An hour after Roger Federer struck a most familiar pose, hoisting that silver trophy over his head, another celebration took place at the U.S. Open.

Novak Djokovic’s family and friends threw him a little party Sunday night, as if he’d won. Made sense, too. Because these days, everyone in tennis is basically playing for second place behind Roger the Great.

“No. 2, No. 3 - it doesn’t matter much,” Federer said. “It’s No. 1 that matters. That’s how it goes.”

In a match that tilted as much on mental strength as shot-making ability, Federer beat back seven set points Sunday in a 7-6 (4), 7-6 (2), 6-4 win over Djokovic for a fourth straight U.S. Open championship and a 12th Grand Slam title.

“He had his chances today, many of them,” Federer said. “You could sing a song about it.”

Or write a novel.

“My next book is going to be called, ‘Seven Set Points,’” Djokovic said, his smile intact.

Federer became the first man since Bill Tilden in the 1920s to win the American Grand Slam four years in a row. Add in his five straight Wimbledon titles, plus his three overall at the Australian Open and he’s two away from Pete Sampras’ record of 14 Slams.

And at 26, he’s in the prime of his career.

“I think about it a lot now,” Federer said of Sampras’ mark. “To come so close at my age is fantastic, and I hope to break it.”

At 20, Djokovic made a strong impression on and off the court, reaching his first Slam final and doing dead-on imitations of Maria Sharapova and Rafael Nadal.

Sharapova sat in Djokovic’s box — “it’s just a friendship,” he insisted — and apparently approves of his rendition.

“She said she’s going to kill me,” the personable Serb said. “Of course, she found it funny. Not offended.”

Djokovic also does one of Federer that’s posted on YouTube. But Federer didn’t exactly smile when asked about Djokovic’s joking.

“I know some guys weren’t happy. I know some guys might think it’s funny,” he said. “He’s walking a tightrope, for sure.”

On Saturday, top-ranked Justine Henin overwhelmed No. 4 Svetlana Kuznetsova 6-1, 6-3 to win her second U.S. Open women’s title and seventh Grand Slam championship. Henin capped a dominating run through the U.S. Open in which she didn’t drop a set and became the first woman to win a major title while beating both Williams sisters along the way.

About an hour after the match, Djokovic walked outside Arthur Ashe Stadium, where a dozen people were waiting for him. They chanted his name, posed for pictures and gave him a bottle of champagne.

Then, they all gathered around for Djokovic to pop the cork. He tried and tried. Somehow, he couldn’t quite finish the job — he needed his dad’s help to twist the top.

It fit, considering how Djokovic’s day went.

“This is the moment we’ve been waiting for our whole life,” said his mom, Dijana. “If he won the first set I don’t know what would happen, but maybe something different.

“Tennis needs a new face. Tennis needs young boys who like to play tennis,” she said. “I don’t have anything against Nadal and Federer, but when it is always these two guys in the final it is boring.”

Djokovic was the last player to beat Federer, winning two tiebreakers at a tournament in Montreal a month ago.

But on center court in front of an overflow crowd of 25,000, it was different. Right before this match, Federer said: “It’ll be interesting to see how he handles the final.”

He was right.

Ahead 6-5, the third-seeded Djokovic took a 40-love lead and served for the first set. He wound up dropping five set points and double-faulted to make it 6-all.

Midway through the tiebreaker, Djokovic put a backhand into the net. He slammed his racket and a little piece broke off — it was quarter-sized string dampener, used to reduce vibration, that was decorated with a yellow smiley face.

“He knows what it feels like to be in that kind of situation. He knows how to cope with the pressure,” Djokovic said. “For me, this is something new.”

Sitting in his chair during the break, Djokovic squashed a water bottle. A couple of ballboys needed to mop up the spill.

Djokovic led 6-5 in the second set and had two chances to win it on Federer’s serve.

No luck this time, either. Djokovic rocketed a shot that went long and challenged the call. The instant replay showed the ball was out by one millimeter.

“I cannot believe,” Djokovic said. “I was asking the crowd what I need to do. Nobody could give me any advice.”

Federer kept up the pressure in the final set.

“He was just mentally better — a little bit. Little bit. It could have been the other way around,” said Djokovic’s coach, Marian Vajda.

Federer earned a Grand Slam-record $2.4 million: $1.4 million for winning the tournament, and a $1 million bonus because he finished atop the U.S. Open Series standings based on performances at hard-court tuneup events.

He’s now reached the final in 10 straight Slams, with his lone losses to Nadal in the last two French Opens.

In this tournament, almost everyone except Nadal took their best shots at Federer. Young John Isner and Andy Roddick brought their booming serves, Nikolay Davydenko ran all over the court and Djokovic showed promise.

“New guys challenging me - this is my biggest motivation out there,” Federer said. “Seeing them challenging me, and then beating them in the finals.”