Jelena Jankovic's fourth-round defeat at Wimbledon on Monday ensured the second week began with yet another shock, completing the cull of the top three women's seeds.

- Images from Day 8

The Serb's wait for a first grand slam final appearance goes on after an error-strewn 6-3 6-2 defeat by Tamarine Tanasugarn, who at 31 was the oldest woman to reach this year's last 16 and now the first Thai quarter-finalist at a grand slam.

Jankovic, who needed running repairs on her left knee, showed only fleeting glimpses of her normally tenacious game against the world number 60 before aiming a verbal volley at tournament organisers who shunted her out to Court 18.

"I was almost playing in the parking lot. I almost needed a helicopter to go to my court," Jankovic, who needed injections in her knee before the match, told reporters.

Her demise means it is the first time since seedings were introduced in 1927 that the top three women's seeds have fallen before the quarter-finals.

Top seed Ana Ivanovic and third seed Maria Sharapova [Images] had their hopes trampled into the Wimbledon turf last week by players ranked in the 100s.

FEW ALARMS

At least the seeding committee can rely on the Williams sisters and Roger Federer [Images] not to fluff their lines.

Venus Williams [Images], seeded seventh this year, continued to pick her way through the carnage with few alarms with a 6-3, 6-4 defeat of teenager Alisa Kleybanova, one of six Russian women to reach the last 16.

With Tamarine next, a seventh Wimbledon singles final is looming on the Venus horizon and sister Serena looks favourite to be on the other side of the net after she followed her older sibling on to Court Two to despatch Bethanie Mattek [Images] 6-3, 6-3.

"I'm very happy to get through," champion Venus Williams told reporters. "The reality now is that everybody comes to grand slams with double vengeance and no match is a given, you have to work for it."

Chinese wildcard Zheng Jie, who ended Ivanovic's tournament in round three, backed up that performance with a solid 6-3 6-4 defeat of Hungary's Agnes Szavay.

She is the second woman from China to reach the last eight at Wimbledon, emulating Li Na's run two years ago. Zheng faces Czech Nicole Vaidisova next after she won 4-6, 7-6, 6-3 against eighth seed Anna Chakvetadze [Images].

All 16 men's and women's fourth round singles matches take place on Monday with world number two Rafael Nadal [Images], who plays 17th seed Mikhail Youzhny, hoping to stay on course for a third consecutive final.

KUZNETSOVA JOINS SCRAPHEAP

Poland's Agnieszka Radwanska completed the destruction of the top four seeds at Wimbledon when she beat Svetlana Kuznetsova 6-4, 1-6, 7-5 in the fourth round on Monday.

The Russian fourth seed led 3-1 in the decider but could not sustain the momementum and bowed out when she dumped the ball into the net on Radwanska's second match point.

Radwanska, seeded 14, will next face twice former champion Serena Williams [Images] for a place in the semi-finals.

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