Novak Djokovic gave further notice that he is ready to challenge the world's top two with victory over Rafael Nadal in the Montreal Masters semi-finals.
Djokovic will try to beat Federer for the first time on Sunday
The Serb beat world number two Nadal 7-5 6-3, and will take on world number one Roger Federer in Sunday's final.
Top seed Federer earlier beat Radek Stepanek 7-6 (8-6) 6-2.
"This is one of the biggest wins of my career," said Djokovic. "I won against him in Miami on this surface and tonight played some impressive tennis."
Djokovic, 20, has rocketed up the rankings to as high as three in the world this year, claiming a Masters Series title in Miami along the way.
He went into Saturday's semi-final with a 1-5 career record against Nadal but broke in the 12th game to take the opening set and again in the eighth game of the second.
"I was trying to be patient but aggressive at the same time," said Djokovic. "Just trying to make the opportunity for myself so I can finish the point.
"I was lucky in some moments but my serve has been really good throughout the week, and especially today in the important moments, and on the break points I was serving my best."
Nadal said: "I said yesterday that he was playing well, to beat Nalbandian and Roddick. Today he played a very, very good match. A very complete match. He was unbelievable.
He's got an all-around game, he's got a good serve and good return
"I played good tennis, but maybe I have to improve a little bit more. But I am not disappointed about my game.
"I played a good week, semi-finals is a good start of the American season on hard courts."
In the first semi-final, Czech Stepanek had Federer at 0-40 on his serve in the seventh game but the top seed fought back and won the set on a tie-break.
Defending champion Federer then cruised through the second set, breaking twice to wrap up victory.
"Stepanek's a good player and I had to come up with some good shots," said Federer.
"He attacked and I had to make some passing shots. I served well today and my game felt good."
Stepanek was happy with his recent form despite the loss.
"I played three top-12 players in four days, so it's a good sign that I'm on my way back," he said. "I'm able to compete with the best ones.
"I think with guys like Roger and Rafa (Nadal), the chances do not come often.
"They are coming maybe once a set, maybe none. So once you get a chance, you have to use it, and I was not able to use that chance."
Federer will be chasing his 50th career title in Sunday's final and has a 4-0 record against Djokovic.
"I think Novak's really playing well at the moment," he said. "He's got an all-around game, he's got a good serve and good return. Always makes you work hard."