Serena Williams congratulates Marion Bartoli at the net after falling to a straight-sets defeat at the hands of the French Wimbledon 2007 finalist.[Source: Wimbledon.com]

Defending champion Serena Williams was eliminated by Marion Bartoli 6-3, 7-6 (6) in the fourth round of Wimbledon yesterday, cutting short her return to grand slam tennis after nearly a year out with serious health problems.

Williams, a four-time winner at the All England Club, saved four match points before the ninth-seeded Frenchwoman closed out the contest by hitting a service winner into the corner. It was Williams' earliest exit here since a third-round loss in 2005.

In a late match, top seed Caroline Wozniacki was upset 1-6, 7-6, 7-5 by Dominika Cibulkova.

Dane Wozniacki, bidding for her first grand slam title, looked to be cruising through to last eight for the first time as she comfortably took the first set against the diminutive 24th seed from Slovakia. But Cibulkova raised her game to take the second-set tiebreak and she stayed with the world No. 1 through a final set riddled with breaks of serve before clinching a shock win on her third match point with a crunching forehand.

Cibulkova will play fifth seed and former champion Maria Sharapova in the last eight.

Bartoli made the Wimbledon final in 2007, losing to Serena's older sister Venus.

Serena missed nearly a year after foot surgery and subsequent blood clots in her lungs. She returned two weeks ago at Eastbourne for the first time since winning the Wimbledon title in 2010.

Unforced errors

Williams had 20 unforced errors yesterday to go with 29 winners, and managed to convert only one of five break points. Bartoli served 10 aces, two more than Williams, and kept down her errors to 17.

It was the first time Bartoli has beaten the American after straight-set defeats in their previous two matches.

"Beating Serena is almost like a dream come true," Bartoli said. "Even though she didn't play for almost one year, she's probably one of the greatest champions in women's tennis.

"For me to be able come back after having three match points and losing this game at 6-5, and still be able to bounce back, it's really huge."

In men's play, fourth-seeded Andy Murray moved into the quarterfinals by beating Richard Gasquet of France 7-6 (3), 6-3, 6-2.

Murray, who has made the semifinals the last two years, is trying to become the first British man to win the title at the All England Club since Fred Perry in 1936.

Bernard Tomic, an 18-year-old Australian qualifier, downed Xavier Malisse 6-1, 7-5, 6-4 to become the youngest man to make the Wimbledon quarterfinals since Boris Becker in 1986.

2004 champion Sharapova made it to the quarters here for the first time in five years, beating China's Peng Shuai 6-4, 6-2 on a sweltering day.

Sharapova started slowly before winning seven straight games to take command against the 20th-seeded Chinese player in an early match on Court 2. The big-hitting Russian had 27 winners and 10 unforced errors.

Also, fourth-seeded Victoria Azarenka beat Nadia Petrova 6-2, 6-2. German wildcard Sabine Lisicki reached the quarters for the second time, downing Petra Cetkovska 7-6 (3), 6-1. No. 8 Petra Kvitova, a semifinalist here last year, needed just 45 minutes to defeat No. 19 Yanina Wickmayer 6-0, 6-2.