Roger Federer remains on course for a fifth successive US Open crown after battling past Novak Djokovic in four sets in the semi-finals.
The world number two looked in sparkling from in the first set and, after losing his serve twice in the second to allow the Australian Open champion to restore parity, Federer showed his true quality to run out a 6-3 5-7 7-5 6-2 winner.
Trying to salvage what has been a poor year by his lofty standards, the victory - in a rematch of last year's final - extends the four-time defending champion's winning streak at Flushing Meadows to 33 matches.
Both men held their opening services games in impressive fashion but Djokovic couldn't repeat the dose in his second as Federer's power from the baseline saw him establish a 3-1 cushion.
The 27-year-old did not give the Serbian a sniff of getting back into the opening set, making just three unforced errors in total.
The second set looked like it too would hinge on the fourth game, but turned out to be a slightly more topsy-turvy affair.
Djokovic capitalised on his first break-point of the match as Federer - appearing in his 18th straight grand slam semi-final - sent a backhand wide to hand the 21-year-old a 3-1 lead which became 4-1 when he held serve in the next game.
However, Federer battled back to 4-4 but then at 5-6, having already saved two set points, pulled a forehand wide to hand the Serbian the set.
Federer, who had been world number one for a record 237 straight weeks before losing the honour to Rafael Nadal on August 18, headed into this semi-final knowing defeat would see him slip to number three in the rankings behind Djokovic.
But, after the third set went with serve up to 5-5, the 12-time grand slam champion raised his level to secure a crucial break en route to taking the set 7-5.
This is the first time since 2002 that Federer has come into the US Open without having captured at least one grand slam title during the calendar year.
He lost to Djokovic - the eventual champion - in the semis of the Australian Open and was beaten by Nadal in both the French Open and Wimbledon finals.
There was to be no repeat of that success for the Serbian, though, with a couple of backhand errors gifting Federer a break in the fifth game of the fifth set.
Federer never looked likely to relinquish that advantage and did not lose another game - racing to the finish to clinch his place in a fifth successive US Open final, where he will face either Rafael Nadal or Andy Murray.
US Open, Men's Semi-Final result, Flushing Meadows
2-Roger Federer (Switzerland) def. 3-Novak Djokovic (Serbia) 6-3 5-7 7-5 6-2