Wimbledon, England -- (Sports Network) - Top-seeded Dinara Safina moved on, while Venus Williams continued her quest to win a third consecutive Wimbledon title with a third-round victory on Saturday. Big upsets came when French Open champion Svetlana Kuznetsova and U.S. Open runner-up Jelena Jankovic exited the women's draw.

The French Open and Australian Open runner-up Safina bested Belgian Kirsten Flipkens 7-5, 6-1 on Court 2 at the All England Club. Safina moved on in 1 hour, 29 minutes despite misfiring for 21 unforced errors. The big Russian, however, also piled up four service breaks while holding her serve throughout the bout on Day 6.

Safina's fourth-round opponent on Monday will be former Wimbledon champion Amelie Mauresmo.

The third-seeded Williams overpowered Spaniard Carla Suarez Navarro in the first set, then closed out the match strong, taking the final three games on the way to a 6-0, 6-4 win on Centre Court. Williams is riding a 17-match winning streak at the AEC.

The seven-time major titlist Williams, who has won five Wimbledon singles titles this decade, avenged a loss to Suarez Navarro in the second round of the Australian Open back in January.

The former world No. 1 Williams' triumph sets up a fourth-round match with 13th-seeded Serb and fellow former top-ranked star Ana Ivanovic, who downed 18th-seeded Australian Samantha Stosur, a surprise French Open semifinalist this month, 7-5, 6-2.

Meanwhile, a fifth-seeded Kuznetsova was knocked out by big-serving unseeded German Sabine Lisicki 6-2, 7-5 on Court 1.

Lisicki needed five match points to finally put Kuznetsova away. The German almost blew a big lead in the second set, as she led 5-2 before her Russian counterpart mounted a bit of a comeback.

The birthday girl Kuznetsova appeared as though she was on her way to forcing a second-set tiebreak, as the Russian was serving at 5-6, 40-love, but Lisicki fought back to break the Russian and reach her first-ever fourth-round match at a major.

"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."

The former U.S. Open champion Kuznetsova, who turned 24 here on Saturday, captured her second major title three weeks ago in Paris.

A sixth-seeded Jankovic was stunned by unseeded American teenager Melanie Oudin, as the 17-year-old qualifier from Marietta, Georgia recorded a 6-7 (8-10), 7-5, 6-2 victory on Court 3.

"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."

The struggling Jankovic, who needed a long tiebreak to win the first set against the game Oudin, then took a lengthy medical timeout -- in which she lay on the court with a blood pressure cuff on her arm, at one point -- before resuming play. The former No. 1 Jankovic, of Serbia, required medical attention on two occasions before bowing out on Saturday.

Jankovic said she was struggling, in part, because of "woman problems."

"It's not easy being a woman, you know, sometimes," Jankovic said. "After the first set, I felt really dizzy, and I thought that I was just going to end up in the hospital. I started to shake. I was losing my, how you say, consciousness."

"I came back, like I started to feel a little bit better. But I was feeling quite weak. No power. I wasn't the same player."

Jankovic opened the year at No. 1, but has struggled for most of the season and has since dropped down to No. 6.

Ninth-seeded rising Dane Wozniacki avoided the upset bug by easily defeating 20th-seeded Spaniard Anabel Medina Garrigues 6-2, 6-2. Wozniacki was a titlist at Eastbourne last week and is 8-0 on grass this year.

The aforementioned Mauresmo posted a mild upset by taking out 15th-seeded Italian Flavia Pennetta 7-5, 6-3. The 17th-seeded Mauresmo is a former world No. 1 who captured Wimbledon three years ago for her second major title.

Eleventh-seeded Pole Agnieszka Radwanska moved into the round of 16 with a 6-4, 7-5 decision over 19th-seeded Chinese Li Na.

Monday's other fourth-rounders will pit second-seeded Serena Williams against Slovakian Daniela Hantuchova; fourth-seeded Elena Dementieva versus fellow Russian Elena Vesnina; eighth-seeded Belarusian Victoria Azarenka against 10th-seeded Russian Nadia Petrova; Wozniacki versus her fellow youngster Lisicki; Radwanska against the upstart Oudin; and 26th-seeded Frenchwoman Virginie Razzano versus Italian Francesca Schiavone. The reigning Aussie Open and U.S. Open titlist Serena was last year's Wimbledon runner-up to Venus and titled here in 2002 and 2003 for two of her 10 career major titles.

The players will be idle here on Sunday, as the first Sunday is the traditional off day at the AEC. All 16 remaining women will take to the courts on Monday.