Venus and Serena Williams — plus Caroline Wozniacki — are victims of upsets at Wimbledon

Venus Williams joined her sister Serena as a fourth-round loser Monday, and neither of those losses was technically as big an upset as the one suffered by top-seeded Caroline Wozniacki.

Venus lost 6-2, 6-3 to Tsvetana Pironkova, who had beaten Venus here last year as well. Top-seeded Wozniacki was surprised by 24th-seeded Dominika Cibulkova of Slovakia 1-6, 7-6 (5), 7-5.

Earlier, defending champion Serena Williams couldn’t survive a fifth match point and lost to France’s Marion Bartoli 6-3, 7-6 (6).

Serena and Venus had combined to win nine of the last 11 Wimbledons, but neither had played much tennis this year.

Venus, 31, missed 5 1/2 months after suffering a hip flexor at the Australian Open, and Serena, 29, had missed over 11 months with foot injuries and a pulmonary embolism before she returned to play one warm-up before Wimbledon.

One of those who sneaked a Wimbledon title away from the Williams sisters, 2004 champion Maria Sharapova, moved into the quarterfinals with a 6-4, 6-2 win over 20th-seeded Peng Shuai. Sharapova could have been looking at matches against Wozniacki in the quarterfinals and Serena in the semifinals.

Bartoli, who lost to Venus in the finals here in 2007, won the match against Serena with an ace into the corner against the four-time champion.

“Beating Serena is almost like a dream come true,” Bartoli said. “Even though she didn’t play for almost one year, for me to be able to come back from losing the game at 6-5, it’s really huge.”

“I never came here thinking I could lose,” Serena said after her first career loss to Bartoli. “Today I lost but I was able to kind of hang in there and play tough. I can only get better. And that can potentially be really scary because I can only go up from here and I can just do so much more.”

Serena played on Court 1 while British hopeful Andy Murray was beating Richard Gasquet 7-6 (3), 6-3, 6-2 on Centre Court, and when the score of Serena’s loss was put up there, the crowd cheered.

Bartoli served for the match in the 12th game of the second set, but after Serena saved three match points, she got the service break she needed with a ferocious backhand return winner off a 76-mph second serve and seemed to carry the advantage into the tiebreak.

And Serena grabbed an early advantage in the tiebreak when Bartoli missed an easy backhand to give Serena a mini-break and a 2-1 lead, but when Serena served the next time, in playing defense, she put a drop shot into the net.

With the tiebreak at 6-6, Serena made a sloppy backhand error to put herself down 6-7 in the tiebreak, and it was then that Bartoli very carefully practiced her service motion while never looking in the direction of Serena.

“She is very imposing,” Bartoli said. “I wanted to stay in the moment.” The moment was the perfect serve.

It ended the hopes of Serena Williams to make a triumphant comeback after an 11-month absence from tennis due to two foot injuries and a pulmonary embolism. Serena gave Bartoli a hug at the end but then put her head in a towel. Serena had cried after winning her first-round match here on Centre Court last Tuesday, but she didn’t shed tears Monday. She just packed up her rackets and left Court 1.

Wozniacki, despite her No. 1 computer ranking, is still without a major tournament victory. She called the loss to the 5-foot-3 Cibulkova “very disappointing.”

diane.pucin@latimes.com

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