World No. 1 Roger Federer and British teen Andy Murray advanced to the quarter-finals of the ATP Masters Series event on Thursday, but defending champion and second seed Rafael Nadal was ousted.
Reigning Australian Open and Wimbledon champion Federer fought off a challenge to beat Russia's Dmitry Tursunov 6-3, 5-7, 6-0 while Murray downed Spain's Carlos Moya 6-2, 6-4.
Spaniard Nadal lost to 14th-ranked Czech Tomas Berdych 6-1, 3-6, 6-2 in the biggest upset of the third round at the US$2.5 million event, a warm-up for the US Open, the year's final Grand Slam tournament.
Federer dropped a set to Tursunov, a finalist at Los Angeles two weeks ago, but dominated the third set to make it clear he remains the man to beat.
"I thought the match was a good standard," Federer said. "I had my opportunities to win the first set more easily. He hung in there. That was a sign of confidence. I stayed tough in the third set and won it."
The Swiss star said his rhythm was thrown off when he tried to disrupt Tursunov in the second set.
"I broke my own rhythm doing that," Federer said. "I have to be a little more focused on what I'm doing."
Federer advanced to a Friday matchup with Belgian Xavier Malisse, who eliminated Sweden's Thomas Johansson, 7-6 (9/7), 6-3.
By eliminating French Open champion and Wimbledon runner-up Nadal, 20-year-old Berdych booked a date with Frenchman Richard Gasquet, who defeated Spain's Fernando Verdasco 6-0, 4-6, 6-2.
"I was playing one of my best matches," Berdych said. "I was almost perfect. I was putting pressure on Nadal."
Murray, in his second week working with new coach Brad Gilbert, dominated his Spanish foe but struggled when serving for the match before claiming the second set.
"It was one of those things," Murray said. "I've never had a problem with it before. It must just be Toronto."
Murray said tactics and strategy have been the main areas where Gilbert has helped him improve, saying there was too little time to work on other areas of his game before the US Open, which begins later this month.
"The game plans have been really good and I've played well," Murray said. "I thought I took the game too him pretty well and won 90 percent of the points when I was up there. I used my forehand pretty well."
Murray advanced to a quarter-final against Finland's Jarkko Nieminen, who outlasted Italy's Davide Sanguinetti 3-6, 6-3, 7-6 (10/8).
Chile's Fernando Gonzalez pulled the day's other shocker, defeating fourth seed Ivan Ljubicic of Croatia 6-4, 6-7 (4/7), 7-6 (7/3).
He will face Jose Acasuso in an all South American quarter-final after the Argentine player eliminated France's Julien Benneteau 6-3, 7-6 (7/4).
Serena Williams avenged her Australian Open loss to Daniela Hantuchova on Thursday with a 1-6, 6-3, 6-3 victory over the seventh-seeded Slovakian to reach the quarter-finals of a WTA hardcourt tournament.
While Williams had to rally to ease the sting of that defeat in Melbourne, top-seeded Russian Maria Sharapova rolled into the quarters to set up her own grudge match against the woman who ousted her from the French Open -- fifth-seeded compatriot Dinara Safina.
Williams, a seven-time Grand Slam champion, who was dethroned by Hantuchova in the third round in Australia, spent the next six months on the sidelines nursing a nagging knee injury.