Second seed Federer beat his fellow Swiss 6-4 6-3 6-1 to reach the final without losing a set, and having dropped serve just twice.

The 34-year-old goes on to face top seed Djokovic, who thrashed defending champion Marin Cilic 6-0 6-1 6-2.

It will be the first US Open final since 2009 for Federer.  Djokovic, 28, has the opportunity to claim his 10th major title and third of the year, the Serb having won the Australian Open and Wimbledon but lost in the French Open final.

"Novak has had a tremendous year," said Federer, a 17-time Grand Slam champion. "There's always a lot on the line when we play.

"He's the best mover on the hard courts, he's tough mentally, but I like that challenge and I'll be ready for it."

The Swiss has won 18 sets in a row at Flushing Meadows, and 28 without reply since he lost the Wimbledon final to Djokovic.

Federer's swashbuckling form has been the talking point of the men's draw, and especially his new tactic of occasionally stepping in to return almost from the service line, dubbed SABR (Sneak Attack by Roger').

He used it to good effect as early as the third game against Wawrinka, winning one point and losing another behind the net rush, but doing enough to unsettle his compatriot and break serve.

It looked as though Wawrinka would level three games later when he moved 0-40 clear, but Federer smacked an ace down the 'T' on his way to recovering the deficit.

Wawrinka, seeded fifth, had made just 39% of first serves and converted none of his four break points in losing the first set, and his challenge faded late in the second.

Federer got the key break at 4-3 and broke again for a two-set lead, before rattling off 15 of 16 points as he moved 4-1 clear in the third.

When the former champion's defensive skills won him a fifth break of the night, the game was up for Wawrinka, and Federer wrapped up the win in just 92 minutes.

The world number one needed seven minutes fewer to see off Cilic, who was comprehensively outmanoeuvred as he struggled with an ankle injury.

It was the most one-sided men's semi-final in New York since the open era began in 1968.

Croatia's Cilic, seeded ninth, had rolled his ankle injury in an earlier round and came up against the worst possible opponent, with Djokovic breaking his serve eight times.

"Marin was carrying an injury, he was courageous to come out and finish the match, so applause to him," said Djokovic.

"I came out with good focus and good intensity and executed the game plan."

It is the first time in his career that Djokovic has made all four major finals in a single year and he would be competing for the calendar Grand Slam on Sunday, had he not lost to Wawrinka at Roland Garros in June.

"It is a great achievement and I'm very proud of it," he said.

 Courtesy BBC