NEW YORK -- Facing two match points against a beloved player whose name is already in the history books, Novak Djokovic clenched his jaw, nodded his head and flashed an ever-so-slight glimpse of a smile.
"I would lie if I say I didn't think I'm going to lose," Djokovic said.
Might as well go down swinging then, right?
He turned violently on a wide, 108 mph serve from Roger Federer for a cross-court, forehand winner that barely nicked the line. The fans in Arthur Ashe Stadium, ready to explode for a Federer victory, instead found themselves taking a cue from Djokovic -- who raised his hands, asking them to pump up the volume, and give him a little more love.
About 10 minutes later, those fans were dancing with Djoko as he boogied at center court to celebrate an epic U.S. Open semifinal win -- one in which he dug out of a two-set hole, then saved two match points to beat Federer for the second straight year.
Top-seeded Djokovic won 6-7 (7), 4-6, 6-3, 6-2, 7-5 Saturday to improve to 63-2 on the year and set up a rematch in the final against No. 2 Rafael Nadal, who beat No. 4 Andy Murray 6-4, 6-2, 3-6, 6-2 in the second semifinal.
In the first match, Djokovic completed only his second career comeback from two sets down, while Federer lost a two-set lead for the second time in less than three months after going 178-0 lifetime before this year's Wimbledon quarterfinals.
It all turned on one shot.
"The forehand return, I cannot explain to you because I don't know how it happened," Djokovic said. "I read his serve and I was on the ball and I had to hit it hard, and it got in, luckily for me."
Nadal beat Djokovic in the final last year, but Djokovic is 5-0 against the Spaniard this year. All the meetings have been in tournament finals, including Wimbledon. On Monday, Nadal must try to stop the losing streak against a player who will come into the final on the high of a win he called definitely the biggest of the year and "one of the biggest wins of the career under the circumstances."
"He's obviously the favorite for the final, and I know I have to do something better than the other matches to try to change the situation," Nadal said.
Djokovic spent much of the first two sets shaking his head, commiserating with the folks in his players box, even folding his hands in mock prayer. Then, he turned things around suddenly and unexpectedly.
He got an early break in the third to capture the momentum, and as the match wore on, the prospect of Federer grabbing it back, let alone getting a match point, seemed bleak.
In the fourth set, Djokovic placed 16 of 20 of his first serves in and tore off his first 15 service points to easily push the match to the distance.
The fifth-set end-game started with Djokovic serving at 3-4 and stringing together an uncharacteristically bad game, getting broken at love on two mishit forehands, a framer of Federer's that set up a winner and a double fault on a second serve that missed the line by about a foot.
After missing a backhand to open his service game at 5-3, Federer hit three straight serves Djokovic couldn't get back. That gave him two match points, same as he had last year against Djokovic in the semifinals, and the fans were squarely on his side, as he stood oh-so-close to making his 24th Grand Slam final and moving a win away from adding to his record 16 Grand Slam titles.
But Djokovic isn't putting together one of the greatest seasons in tennis history for nothing. And Federer wasn't totally convinced the shot that turned the match was legit. He said the Djokovic winner reminded him of shots hit by players he played as a kid -- who fall behind, then start taking huge chances when they feel they have nothing else to lose.
"I never played that way," Federer said. "I believe in the hard-work's-going-to-pay-off kind of thing, because early on, maybe I didn't always work at my hardest. So for me, this is very hard to understand how can you play a shot like that on match point. But, look, maybe he's been doing it for 20 years, so for him it was very normal. You've got to ask him."
But Federer couldn't put it away on his second match point, either.
There, his serve hit the back of the line and jammed Djokovic, but somehow Djokovic got it back. Federer cranked a forehand, but it ticked the net and ricocheted out. Federer sprayed a forehand wide at deuce and suddenly, a crowd gearing for a Federer win was shouting "No-vak! No-vak! No-vak!"
Djokovic said it was no insult that the fans had been behind Federer, who makes some kind of history seemingly every time he steps on a court.
Still, the current world No. 1 wasn't giving up on capturing their hearts. Which was why he made a scene between the match points -- an awkward time for showmanship, though one Federer said he had no problem with.
"At that stage, you're trying to get as much support as you can," Djokovic said. "You're trying to get energy."
Stoked with that energy, Djokovic won the last four games and, counting the two match points he saved, he took 17 of the final 21 points.
The match took 3 hours, 51 minutes, while Nadal's win was a 3 hour-24 minute affair.
But thanks to the rain that scrubbed two days of play from this tournament and reshuffled the schedule, Djokovic and Nadal will get a day's rest between the semifinal and the Monday final. It's a break from the long U.S. Open tradition of closing things out on back-to-back days on the weekend.
Murray and Nadal were each playing their third match in three days and the toll showed more on Murray, who had the tougher road.
"We knew it was going to be like that for quite a few days and just tried to get through it and deal with it the best way we could," Murray said. "But it was never going to be easy."
Fittingly, given how things have gone lately, the start of the Federer-Djokovic semifinal was delayed for about an hour because showers began falling shortly before the players were supposed to walk on court, which had "9/11/01" painted in white to commemorate the 10th anniversary of the Sept. 11 attacks.
In the men's opener, Djokovic avenged one of his only two losses this season. He fell to Federer in the French Open to snap a string of 43 straight victories -- the third-longest win streak in the Open era.
Federer, meanwhile, was trying to win at least one Grand Slam tournament for the ninth straight season and appeared more than ready to keep the quest alive.
For two sets, at least.
After that, Djokovic turned into a steamroller, leaving the unmistakable feeling that a shift of power was being completed -- from Federer, who won three Grand Slam tournaments each in 2004, 2006 and 2007, to Djokovic, who is trying to do it this year, along with Nadal, who is still very much in that mix.
Nadal and Djokovic will meet for the third time over the last five Grand Slam finals.
But even with the loss, Federer showed he's not done.
To move within a point of the match after the way Djokovic played the third and fourth sets was a testament to what the 30-year-old still has left in the tank.
"I did all the right things in so many tournaments," Federer said. "But like I said, sometimes in sports it just goes the other way. Maybe you've already won so much that it evens it out a bit sometimes. I don't know."