American teenager Melanie Oudin pulled off the biggest upset of the first week at Wimbledon yesterday beating former No. 1 Jelena Jankovic, 6-7 (8), 7-5, 6-2.

The No. 6-seeded Jankovic struggled with the heat on a sunny, 82-degree afternoon, and took a 12-minute break after the first set. The 2008 US Open runner-up also needed treatment of her left foot later, and she was plagued by erratic groundstrokes, while the 17-year-old Oudin played with poise down the stretch and swept the final three games.

"I was just thinking that she was any other player," Oudin said, "and this was any other match, and I was at any other tournament - not like on the biggest stage at Wimbledon. I think I handled it really well."

joined by Williams

Five-time champion Venus Williams joined Oudin in the round of 16 by beating Carla Suarez Navarro 6-0, 6-4.

Oudin's so young her earliest Wimbledon memory is watching the Williams sisters on TV.

"When I was like seven, when I started playing tennis, I saw Venus and Serena Williams playing here and I was like, 'Mom, I really, really want to play there one day,"' Oudin said. "She said, "Go for it.' My parents have always been very supportive."

In men's play, 2002 champion Lleyton Hewitt reached the fourth round for the sixth year in a row by beating Philipp Petzschner 7-5, 7-6 (3), 6-3. Third-seeded Andy Murray, seeking to become the first British man to win Wimbledon since 1936, also advanced by defeating No. 30 Viktor Troicki 6-2, 6-3, 6-4.

A few drops of rain fell during that match, but there was no halt in play, and the new retractable roof on Centre Court remained unneeded for a sixth consecutive day.

Two-time runner-up Andy Roddick advanced after hitting the last of his 33 aces on match point to beat good friend Jurgen Melzer 7-6 (2), 7-6 (2), 4-6, 6-3.

The No. 6-seeded Roddick is 22-3 in tiebreakers this year, and he improved to 9-0 against Melzer. Roddick's opponent Monday will be No. 20 Tomas Berdych, who eliminated No. 12 Nikolay Davydenko 6-2, 6-3, 6-2.

Lisicki's splash

Oudin wasn't the only teen to make a splash on the final day of the first week. Unseeded 19-year-old Sabine Lisicki of Germany upset No. 5 Svetlana Kuznetsova, the French Open champion, 6-2, 7-5.

"Before I came into this Wimbledon championships, I hadn't won, actually, a match on grass," Lisicki said. "I just can't believe I'm in the fourth round."

No. 9-seeded Caroline Wozniacki, 18, reached the fourth round for the first time by beating No. 20 Anabel Medina Garrigues 6-2, 6-2. No. 11 Agnieszka Radwanska earned a chance to play Oudin on Monday by beating No. 19 Li Na 6-4, 7-5.

Top-ranked Dinara Safina, enjoying her best Wimbledon, beat Kirsten Flipkens 7-5, 6-1. No. 17 Amelie Mauresmo, the 2006 Wimbledon champion, defeated No. 15 Flavia Pennetta 7-5, 6-3.

Facing a top-10 opponent for the first time, the 124th-ranked Oudin wore down Jankovic in an arduous first set. Oudin failed to convert four set points, committing an unforced error each time, but when the 66-minute set ended, it was Jankovic who appeared on the ropes.

A trainer and doctor came on court to check Jankovic's pulse and blood pressure. She rested on a towel while being treated, and after several minutes sat up while ice was applied to her neck and midsection.