Jelena Jankovic avoided a black day in Wimbledon women's history on Saturday, while four-time champion Venus Williams joined the Serbian world number two in the last 16.

Second seed Jankovic came from behind to beat Danish 30th seed, and 2006 junior champion, Caroline Wozniacki 2-6, 6-4, 6-2 to make the fourth round for the third successive year.

Had she lost, it would have been the first time in Wimbledon history that all three women's top seeds had been knocked out before the end of the first week.

She avoided the fate suffered by Ana Ivanovic and Maria Sharapova, but her third round win came at a cost with the 23-year-old picking up a left knee injury which puts a question mark over her fourth round match with Thai veteran Tamarine Tanasugarn.

"I slipped and my leg went straight. I started to feel some pain. It was a struggle so I needed treatment," said Jankovic.

"The physio taped it but I couldn't move. I had to take the tape off. The physio wasn't happy about that. Now I will have to see how it will react and I'm just hoping for the best."

Williams moved closer to a fifth Wimbledon title and joined sister Serena in the last 16 with a 6-1, 7-5 victory over Maria Jose Martinez.

The reigning champion and seventh seed will face Russian Wimbledon debutant Alisa Kleybanova, who put out Japanese veteran Ai Sugiyama 6-4, 6-4 for a place in the quarterfinals.

Williams reeled off the first five games in just 17 minutes before her Spanish opponent rallied but then closed out the match with a 127 mph serve which equalled her record best.

"It's a blessing to be able to serve like that and it was a good way to end the match," said the 28-year-old American.

"I never try to do serves that hard. It's just what I do. It just comes big to me."

Tamarine, 31, staged a superb fightback to reach the fourth round for the seventh time with a 4-6, 6-4, 6-4 win over New Zealand's Marina Erakovic.

The Thai, who won the warm-up event at 's-Hertogenbosch last week after coming through qualifying, shocked Vera Zvonareva, the Russian 13th seed, in the last round.

Russia's Alla Kudryavtseva, the world 154 who put out Sharapova, reached the fourth round of a Grand Slam for the first time with a 6-3, 1-6, 6-4 win over China's Peng Shuai and faces compatriot Nadia Petrova next.

Russian fifth seed Elena Dementieva also went into the last 16 with a 7-6 (7/2), 7-5 win over Argentina's Gisela Dulko.

Meanwhile, Germany's Rainer Schuettler, the oldest man left in the men's draw at 32, reached the fourth round for the first time since 2003 with a 6-2, 6-3, 6-4 win over Spain's Guillermo Garcia-Lopez.

Schuettler, now 94 in the world after reaching a career high of five in 2004, will face Janko Tipsarevic of Serbia for a place in the quarterfinal.

Tipsarevic, who put out sixth seed Andy Roddick in the last round, defeated Russia's 25th seed Dmitry Tursunov 7-6 (7/1), 7-6 (7/3), 6-3.

Second seed Rafael Nadal has a chance to rescue Spanish pride against a German opponent on the eve of the Euro 2008 football final when he meets Nicolas Kiefer in his third round match later Saturday.

Britain's Andy Murray, the 12th seed, faces Germany's Tommy Haas in a bid to keep home hopes alive.

AFP