London, England (SportsNetwork.com) - Top seed Stan Wawrinka eased into the quarterfinals, while Andy Murray will not defend his title after suffering an upset Thursday at the $965,000 Aegon Championships.
Fifteenth-seeded 35-year-old Czech veteran Radek Stepanek stunned the third- seeded Murray in 7-6 (12-10), 6-2 fashion at The Queen's Club. Murray was playing his first tennis this week with his new coach, Amelie Mauresmo.
"I thought the first set was a pretty high standard," said Murray. "I thought he served pretty well throughout the whole match.
"I have only got myself to blame that I lost the first set. I don't know how many set points I had, but quite a lot of them were on my serve.
"On this surface especially you shouldn't really be losing sets like that. For me, that's what's disappointing about the match. And then unfortunately I got broken in the first game of the second set. I couldn't quite get it back.
"The tiebreak was tough."
The reigning Wimbledon champion Murray is a three-time Queen's Club titlist, including last year when he beat Croat Marin Cilic in the grass-court final at this Wimbledon tune-up.
Murray hasn't reached a final anywhere since giving Britain its first male singles champion at Wimbledon in 77 years last July. He had won his last 19 matches on grass since losing to Roger Federer in the 2012 Wimbledon finale.
The Australian Open champion Wawrinka cruised past American Sam Querrey 6-2, 6-2, while second-seeded former Wimbledon runner-up Tomas Berdych also avoided a third-round upset by getting past France's Adrian Mannarino 7-6 (7-2), 6-4. Querrey was the Queen's Club champ in 2010.
Mannarino fought off 17 break points, including four set points at 6-5 in the first set, before Berdych broke on his 18th break point to lead 2-1 in the second.
Berdych's quarterfinal opponent on Friday will be 10th-seeded Spanish left- handier Feliciano Lopez, who outlasted Frenchman Kenny De Schepper 7-6 (7-3), 6-7 (4-7), 7-6 (7-3) on Day 4.
Another upset occurred when Aussie Marinko Matosevic toppled fifth-seeded French star and 2011 Queen's Club runner-up Jo-Wilfried Tsonga, 6-2, 6-4. Matosevic is rewarded with a match against the Swiss slugger Wawrinka.
Meanwhile, fourth-seeded rising Bulgarian Grigor Dimitrov grounded Frenchman Edouard Roger-Vasselin 7-6 (7-3), 6-4, seventh-seeded South African Kevin Anderson snuck past Ukrainian Sergiy Stakhovsky 6-3, 3-6, 7-6 (7-4) and eighth-seeded Ukrainian Alexandr Dolgopolov was beating Jarkko Nieminen 6-4, 4-2 when the veteran Finnish left-hander retired.
Friday's other quarterfinals will pit Dimitrov against Dolgopolov and Anderson versus Stepanek.