A swing of the forehand here, a gliding backhand there; a textbook volley here, and precision-missile-would-be-jealous-serve there and Roger Federer was into the final of the US Open 2015, making mincemeat out of his compatriot and great friend Stanislas Wawrinka.

Federer came into the semifinal in ridiculous form, and he stepped that form up another level, making Wawrinka look like an unseeded, qualifier who was just happy to be in a semifinal, rather than the two-time Grand Slam winner, who had swept aside the great man in the French Open earlier this year.

The results of that swing, glide, textbook and precision-missile-would-be-jealous was an as comfortable as they come 6-4, 6-3, 6-1 victory, which means there is that mouth-watering final – Roger Federer vs Novak Djokovic -- now awaiting everyone.

Wawrinka admitted he had just been beaten by the better man, even if the faster court at the Arthur Ashe Stadium in the night made it all the more difficult.

"The way he's playing. Condition a little bit different than when I play my match here on Ashe," Wawrinka said. "It's a little bit more flying in the night. It's playing really fast.

"Didn't play my best game. Didn't serve well and everything.

"But basically it's him, the way he's playing."

Federer might be a grand old man in terms of tennis age, but, yet again, in this semifinal the 17-time Grand Slam showed all that age this is, is a number, moving around the court with consummate ease – when he wasn't giving Wawrinka the runaround, that is.

"He's moving really well, for sure," Wawrinka added. "As I said before playing him, I saw him in Cincinnati, I think he's quite fast on the court.

"He's reading well the game, and so he's trying really to stay on the line, not to go back. Stay really aggressive. He's serving really well, also. He's serving better than I never see him serve.

"For me, [in this semifinal] he's getting more angles. It's more tough to really serve and to make something from."