Roger Federer produced a tennis masterclass to turn the tables on Rafael Nadal and earn a place in the final of the Masters Cup in Shanghai.
Federer has now won three of his nine matches against Nadal
He will face James Blake on Sunday after the American beat defending champion David Nalbandian 6-4 6-1.
In the first of the semi-finals, Federer's only blip came when serving for the first set at 5-3 but he broke straight back to take the advantage.
A single break in the second set completed a 6-4 7-5 victory.
World number two Nadal had won six of the pair's previous eight meetings, but Federer dominated from the off and dictated the tempo throughout.
"It's a great challenge for me because he's one-dimensional, he always plays the same way but he does it so well," Federer said of Nadal.
"It's a big test for me and I'm happy to come through.
It was a good feeling, usually I only have that for finals
"These are matches I'm waiting for, to beat the best who are coming after me and I beat him in the last game (between them) of the season."
Nadal said: "It's a special match, the number one against the number two. Roger is playing at an unbelievable level - I am not so far from him today."
Federer quickly opened up a 3-0 lead and had break points for a 4-0 lead in the first set.
Nadal was unable to match Federer's quality but dug in in typically gritty fashion to at least stay in the match.
And his tenacity was rewarded when Federer lost his focus when serving for the first set at 5-3.
The world number one hit three straight errors, including a routine volley, to fall 0-40 down, and Nadal took the first chance to break back.
I have no pressure against Federer, absolutely nothing to lose
Nadal then came out firing, but Federer showed his defence can match his peerless attack and he snuffed out the Spaniard's comeback by breaking straight back to take the set.
The second set was a closer affair, but Federer always looked the more likely to get the crucial break.
Nadal saved two match-points when serving at 4-5, but he was unable to repeat the trick at 5-6.
Federer clinched victory with the point of the match, chasing down Nadal's pin-point drop and firing a blistering winner out of the Spaniard's reach into the corner.
"It was a good feeling, usually I only have that for finals," he said. "I rarely finish my matches like this so it was nice."
The victory gave Federer a fourth straight appearance in the Masters Cup final, a feat only previously achieved by Ivan Lendl.
Blake broke Nalbandian twice in the first set and three times in the second, hitting 26 winners against 12 from the Argentine.
"Today's match definitely was not easy," said Blake.
"But it seemed like every one of those shots where you just make a stab at it, you kind of hope and pray it goes in - all of those for me were dropping in."
And Against Federer, Blake said he will continue to just go for broke.
"I have no pressure, absolutely nothing to lose," he said. "I think that's when I play my best tennis."