WIMBLEDON, England — Second-seeded Jelena Jankovic and No. 4 Svetlana Kuznetsova were ousted in the fourth round today, leaving Wimbledon without any of the top four women in the quarterfinals for the first time.

A hobbled Jankovic fell 6-3, 6-2 to Tamarine Tanasugarn, while 2004 U.S. Open champion Kuznetsova lost 6-4, 1-6, 7-5 to 19-year-old Agnieszka Radwanska of Poland.

With top-seeded Ana Ivanovic and No. 3 Maria Sharapova eliminated last week, none of the top four women reached the quarterfinals — the first time that's happened at Wimbledon and also the first time at any Grand Slam tournament in the 40-year history of the Open era.

The highest seeded player left is No. 5 Elena Dementieva, who cruised to a 6-2, 6-1 win over Shahar Peer.

The Williams sisters, meanwhile, moved closer to another Wimbledon final with back-to-back victories on Court 2 — nicknamed the "Graveyard of Champions" for its history of upsets. They questioned why they weren't put on Centre Court or Court 1.

Defending champion Venus Williams beat Russian teenager Alisa Kleybanova 6-3, 6-4, while two-time winner Serena downed Bethanie Mattek — the only other American left in the men's or women's draw — 6-3, 6-3.

"It wasn't what I would have liked to see," Serena Williams said of the Court 2 scheduling. "Initially, I thought, 'Is this the right schedule?' I thought maybe there was a mistake. But I can't dwell on that. I just have to focus on doing the best that I can whether I'm on Court 2 or Court 20."

In men's play, five-time champion Roger Federer swept Lleyton Hewitt — the last man to win the title before him — 7-6 (7), 6-2, 6-4 on Centre Court to extend his winning streak on grass to 63 matches and 38 in a row at the All England Club. Federer, who served 21 aces, has now beaten his Australian rival in 12 consecutive matches.

Federer will next face the last player to beat him on grass and at Wimbledon — Croatian Mario Ancic, who won in the first round in 2002. Ancic came from two sets down Monday to beat Fernando Verdasco 3-6, 4-6, 6-3, 6-4, 13-11. The final set alone lasted 1 hour, 35 minutes.

"I completely underestimated him back in 2002," Federer said. "I was a little shellshocked and didn't know what happened to me. What it taught me was not to underestimate any opponent."

No. 2-ranked Rafael Nadal, runner-up to Federer the last two years, overcame an injury scare in the second game of the match and beat Mikhail Youzhny 6-3, 6-3, 6-1.

Nadal slipped on the worn turf behind the baseline on Court 1 while stretching to hit a forehand, with his right leg bending awkwardly. After losing the point, he took a medical timeout, and a trainer wrapped his leg below the knee. The Spaniard lost the next point and the game, but showed no sign of trouble and dominated the rest of the way.

"I felt a little bit of pain," the four-time French Open champion said. "I was a little bit scared. I felt something crack a little behind (the knee). But I think it's fine."

Playing with her left knee heavily strapped, Jankovic was never in serious contention against the 60th-ranked Tanasugarn. The 31-year-old Thai, playing in her 12th consecutive Wimbledon, also was treated for a lower back problem during changeovers in the second set.

After converting on match point to reach the quarterfinals of a Grand Slam for the first time, Tanasugarn covered her face with her hands and broke into tears.

"Wow, wow, wow," Tanasugarn said. "Being in the fourth round so many years, making it to the quarterfinals is really a good feeling."

Jankovic, who complained about being scheduled out on Court 18, said she played with a tear in her knee sustained during her third-round win Friday over Caroline Wozniacki.

"I was always a step behind," said the Serb, who committed 19 unforced errors. "It was very hard for me. I tried the best I could and she was quite solid and didn't make any mistakes. I wasn't moving the way I usually move. I just couldn't play at my best."

No. 10-seeded Marcos Baghdatis, a semifinalist in 2006 and quarterfinalist last year, squandered three match points in the fifth set and lost 5-7, 6-2, 3-6, 7-6 (4), 8-6 to Feliciano Lopez. The Spaniard, down 0-40 at 4-5, came up with big serves on all three points to avoid defeat.

"He just went for it with guts, and he took the game," Baghdatis said. "Good for him."

Venus Williams, a four-time Wimbledon winner, nearly squandered a 5-1 lead in the second set against the 18-year-old Kleybanova. She lost nine points in a row from her third match point in the eighth game and saved three break points at 5-4 before finally closing it with a backhand volley winner.

Serena Williams wobbled slightly after going up 3-0 in the second set as Mattek raised her game by playing serve-and-volley. Williams received a warning for an audible obscenity in the fifth game, but that didn't stop her as she won the next five points. She finished the match with a backhand drop volley into the open court.

Venus Williams, who will face Tanasugarn in the quarters, was clearly not happy with the court scheduling.

"There's not too much I'm going to say about that in the press," she said. "I think that no matter where we play we realize we have to play well. That's pretty much all I have to say."

Her father, Richard Williams, didn't hold back.

"Venus is a four-time champion, defending champion," he said. "They're not putting Roger Federer out there (on Court 2). If they're not putting Roger Federer out there, they shouldn't put Venus out there. I think it's ridiculous. I think it's a damn shame."

All England Club spokesman Johnny Perkins said the tournament referee had to schedule 16 matches on the same day, and noted that Courts 2 and 18 are show courts.

"Spectators on Court 2 have paid for their tickets" and should get to see top players, he said.

Between them, Venus and Serena have won six of the last eight women's singles titles at Wimbledon. They're in opposite halves of the draw and could meet in the final Saturday. The Williams sisters faced each other in the 2002 and '03 finals, with Serena winning both.

Federer, who hasn't lost a set while chasing his sixth straight title, was in complete command against Hewitt after scraping through the first-set tiebreaker. At 7-all, Federer mis-hit a backhand and the ball was ruled wide, but a replay showed it hit the sideline and the point was replayed. Federer then hit a backhand winner for 8-7, and an ace gave him the set.

Hewitt, the 2002 Wimbledon champion whose career has been slowed by a chronic hip injury, went 0-8 on break points.

"I saw Lleyton struggling with his hip a little bit," Federer said. "That first set tiebreaker really put me on the winning streak and after that I played consistently well."

Hewitt, who said he's not sure if he'll play in the Beijing Olympics or U.S. Open because of his hip troubles, praised Federer's serve.

"He hit every line out there today," the Australian said. "That's why he's the best player around, especially on this surface. Serve is so important. He hit the target every time."

Also advancing was Chinese wild-card entry Zheng Jie, who followed up her upset of Ivanovic last week to beat 19-year-old Hungarian Agnes Szavay 6-3, 6-4. Zheng was down 4-1 in the second set and then won five games in a row before securing her first Grand Slam quarterfinal berth.

Other women's winners were Nicole Vaidisova, who downed No. 8 Anna Chakvetadze 4-6, 7-6 (0), 6-3; and Nadia Petrova, a 6-1, 6-4 victor over Alla Kudryavtseva, who had beaten Sharapova in the second round.