PARIS -- Rafael Nadal and Novak Djokovic overcame big servers Thursday to reach the Paris Masters quarterfinals.
Nadal beat last year's runner-up, Jerzy Janowicz, 7-5, 6-4, and Djokovic rallied from a set down to top John Isner 6-7 (5), 6-1, 6-2.
The tournament has turned into a rehearsal for the ATP World Tour Finals, with the eight quarterfinalists also the eight players who qualified for the London tournament next week. Wawrinka and Gasquet grabbed the last two spots at the season ending-event when Berdych eliminated Milos Raonic of Canada 7-6 (3), 6-4.
Nadal broke for a 6-5 lead before whipping a forehand winner down the line to take the first set.
The top-seeded Spaniard and Janowicz traded breaks early in the second set before the Pole double-faulted to hand Nadal a 3-2 lead. The U.S. Open champion won when Janowicz's forehand sailed long.
"I tried to move him, because if he plays in a good position, he has a great shot," Nadal said. "I think for a moment my return was unbelievable today. I returned amazing balls."
Nadal will face Frenchman Gasquet, a 6-3, 6-2 winner over Japan's Kei Nishikori.
Djokovic couldn't find a breakthrough in the first set as Isner saved six break points to force the tiebreaker and won it when Djokovic's backhand sailed wide.
The second-seeded Serb raised his game in the second set, making only two unforced errors and breaking Isner twice.
"I just needed to be very tough mentally and just believe I can make a break," Djokovic said. "I knew as soon as I make a break I'm going to start playing better and relaxed in a way, so that's what happened."
Djokovic won the last five games of the match, finishing off the American with a backhand volley.
Djokovic stretched his winning streak to 14 matches after taking the China Open and the Shanghai Masters titles in October.
"In China, I have had probably the best two weeks of the year, except at the beginning of the year, so it gives me a lot of confidence," Djokovic said. "I feel that I'm back mentally where I need to be, and hopefully I can maintain this winning streak and I can kind of keep on playing better and better."
The Australian Open champion will face Wawrinka, who beat Nicolas Almagro of Spain 6-3, 6-2.
The seventh-seeded Swiss player overcame a 3-1 deficit in the first set and broke Almagro twice in the second.
Federer also moved into the quarterfinals by dismissing Philipp Kohlschreiber of Germany 6-3, 6-4.
The fifth-seeded Federer saved three break points and broke once in each set, improving his record against Kohlschreiber to 8-0.
"I'm just really focused on trying to win as many matches as I can, get some momentum going, and getting in form," Federer said. "I felt good again for the second straight day here in Paris. It's still early in the tournament, and it's a good thing that I feel so good so early. I hope to maintain this kind of a play, and if possible try to get just a touch better."
Federer, who won the Paris Masters in 2011, will meet del Potro in a rematch of last weekend's Swiss Indoors final. The fourth-seeded Argentine overcame Grigor Dimitrov of Bulgaria 3-6, 6-3, 6-4.
Del Potro broke for a 5-4 lead in the deciding set before hitting a forehand winner on match point.
Spain's Ferrer cruised past Gilles Simon of France 6-2, 6-3, to set up a match against Berdych.
Berdych saved three set points in the tiebreaker against Raonic before firing a forehand winner to convert his sixth set point. Raonic dropped serve in the opening game of the second set and lost the match when he sent a forehand return long.