Novak Djokovic won his 15th straight match and Roger Federer avenged last week's loss to Juan Martin del Potro, setting up a semifinal match between the two at the Paris Masters.
Djokovic beat Stanislas Wawrinka of Switzerland 6-1, 6-4, while Federer defeated Del Potro of Argentina 6-3, 4-6, 6-3 Friday.
Top-seeded Rafael Nadal also moved into the semifinals with a 6-4, 6-1 victory over Richard Gasquet of France and will play either defending champion David Ferrer or Tomas Berdych.
Federer earned his first victory over a top-10 player since January, when he outlasted Jo-Wilfried Tsonga in the quarterfinals of the Australian Open.
"That's definitely good for my confidence, because those are the kind of wins I need right now," Federer said. "I'm happy now I won against a top-10 again, especially just before London where I will have to play against three top-10 players in a row."
The eight quarterfinalists at the Paris Masters are the same eight who have qualified for the ATP World Tour Finals in London next week.
Federer lost to del Potro in last weekend's Swiss Indoors final, but the 17-time Grand Slam champion played nearly flawless tennis in the first set, making 17 winners and only four unforced errors.
Del Potro fought back in the second set, saving a break point in the opening game before converting his second break chance at 5-4 to level the match when the fifth-seeded Swiss netted a forehand.
In the deciding set, Del Potro sent a forehand into the net to drop serve at 3-3 and Federer won the match when the Argentine hit a forehand long.
Djokovic, who saved all six break points he faced, won 13 of 19 points at the net.
"Coming to the net is one of the improvements that I had recently," Djokovic said. "It didn't click so fast, trust me. I had to work and put in many, many hours on the practice court that you guys don't see."
Wawrinka lost five-setters against Djokovic at the Australian Open and the U.S. Open this year.
"When he plays that good it's very difficult, especially on this surface where he's the best, I believe," Wawrinka said.
Nadal improved his record against Gasquet to 12-0 despite a crowd cheering loudly for the only Frenchman left in the draw.
The Spaniard, who is seeking a record sixth Masters title in a single season, broke for a 4-3 lead with a crosscourt backhand return winner.
Gasquet struggled with his one-handed backhand against Nadal's powerful groundstrokes. The U.S. Open champion went a set up when Gasquet made a backhand error.
Nadal took a 4-0 lead in the second set and finished off Gasquet with a forehand winner down the line.