Roger Federer conjured a brilliant winner from between his legs to bring up match point as he beat Novak Djokovic 7-6, 7-5, 7-5 in Sunday's semi-final to move within one win of a sixth successive US Open crown.
The Swiss magician will face 20-year-old Juan Martin del Potro of Argentina, the sixth seed, who reached his first Grand Slam final by routing Spain's Rafael Nadal 6-2, 6-2, 6-2.
Federer earned triple match point in the entertaining tussle by racing to the baseline to retrieve a lob from the fourth-seeded Serb and, with his back to the net, whacked a low, crosscourt winner past a stunned Djokovic.
"I was in a difficult position. I had nothing to lose I guess," said Federer, who called the dazzling retrieval the greatest shot he had ever made.
A forehand serve return winner on the next point ended the two-hour 34-minute match.
Djokovic, runner-up to Federer in the 2007 Open, had his chances, but the world number one always rose to the occasion.
"In these moments he comes up with some great shots," 2008 Australian Open winner Djokovic said. "He comes up with very, very precise serves, which give him a lot of advantage, and that's why he's the best in the world.
"I mean that shot he hit," marvelled the Serb. "How can you explain it? It was funny. On these shots, you just say, 'well done, too good.' What can you do?"
Djokovic drew first blood, breaking for 4-2 in the first set. A missed backhand, two forehand errors and a double fault allowed Federer to break right back at love.
"I think that's the worst game I played all match," the loser said. "Who knows? If I was 5-2 up, a lot of things can change."
Instead, the set continued on serve to a tiebreaker.
French Open and Wimbledon champion Federer, aiming to equal American Bill Tilden's feat of six US titles in a row in the 1920s, won it 7-3 by winning five of the last six points.
DUCKED AWAY
The tight second set featured a scintillating exchange of five successive volleys from Djokovic who stretched to deny Federer's passing shots.
After the Serb's last backhand stab floated back across the net, Djokovic turned away and ducked in an act of surrender to avoid getting clobbered by a Federer putaway.
Another tiebreaker appeared to be in the offing until some groundstroke errors from Djokovic allowed the 28-year-old Swiss to cash in his third set point with a forehand winner.
"I had a lot of fun today," Federer said. "I think Novak had a great tournament himself so it was great to come through because it was a tough match."
Federer also congratulated Del Potro and said he expected a good match against the Argentine, who held a two sets to one lead in their Roland Garros semi-final before falling.
"I think he played wonderfully today against Rafa. I think he's proved he's a grand slam contender. He's not in the final for nothing," said Federer, who will be gunning to extend his record of grand slam singles titles to 16.
"I had a tough five-set match against him in the semi-finals of the French Open," added the top seed. "So I'm excited to play against him."
