MELBOURNE, Australia — Roger Federer advanced to the Australian Open semifinals for the ninth consecutive year with a 6-4, 6-3, 6-2 victory over Juan Martin del Potro, one of only two men who've beaten him in a Grand Slam final.
After celebrating his 1,000th tour-level match with an emphatic win Tuesday over the 2009 U.S. Open champion, Federer might have to beat the other one — No. 2-ranked Rafael Nadal — to win his fifth Australian title.
The win, sealed with a trademark backhand winner, sets up the prospect of a semifinal against 10-time major winner Rafael Nadal, who was playing No. 7-ranked Tomas Berdych in a night quarterfinal.
Federer and Nadal are on the same half of the draw at a major for the first time since 2005, and No. 1-ranked and defending champion Novak Djokovic is on the other side.
The women's semifinal on the top half of the draw was decided when defending champion Kim Clijsters beat No. 1-ranked Caroline Wozniacki 6-3, 7-6 (4) after third-seeded Victoria Azarenka fended off Agnieszka Radwanska in three sets.
Clijsters has needed continual treatment since Sunday, when she injured her left ankle and had to save four match points in her fourth-round win over Li Na, a rematch of the 2011 final. The 28-year-old Belgian's win on Tuesday means Wozniacki will lose the top ranking, with Azarenka one of three women who could finish at No. 1 in Melbourne.
"Yeah, instead of really focusing on the match you're focusing on trying to get the ankle as good as possible," Clijsters said of her interrupted preparation. "Laying on the couch, every 20 minutes ice, 20 minutes off, 20 minutes ice, 20 minutes off. Leg elevated. Lymphatic drainage, all that stuff."
Federer had no such worries, using his time to work out how to defuse the big forehand of del Potro, who had beaten him two of their previous three matches. He did a stunning job of shutting down the Argentine's big weapons, relying on his exceptional speed to the ball and full range of shots to ensure 11th-seeded Del Potro never had a chance to get settled.
"I'm very happy. It was a great match," said Federer, who has won four of his 16 majors on Rod Laver Arena. "It was a high quality match and Juan Martin is a wonderful player and I know how hard he can hit the ball."
He planned to watch the Nadal-Berdych match on TV, "even though I know both players very well."
"There's no secrets out there, but I'll still enjoy it. I love good tennis."
Tuesday opened with Azarenka beating No. 8 Radwanska 6-7 (0), 6-0, 6-2 to move into the semifinals of a Grand Slam for the second time and maintain a chance of surpassing the Dane at No. 1.
Wozniacki needed to reach the semifinals to retain the top ranking she has held at the end of the last two seasons. Her place in the rankings has attracted some criticism because she's never won a major.
But even after another major setback, Wozniacki remained confident she'll not only reclaim the top ranking but will get her Grand Slam breakthrough.
"You know, I will get it back eventually, so I'm not worried," she said. Critics "talk to me like I'm finishing my career and I only have one year left and time is running out.
"The fact is I still have quite a few good years in front of me."
Clijsters slipped to No. 14 after beating Li Na in the last Australian final, losing in the second round at the French Open and then missing the next two majors due to injuries. But after losing her first four finals in the majors, she's learned how to win them.
She set an example for Wozniacki of how to go about it.
Both players started nervously, with three service breaks until Clijsters held in the fourth game of their quarterfinal. She dictated play from her first hold until she was serving for the match while a break up in the second.
She had the rally on her racket at 30-30, but let her guard down and allowed Wozniacki back into the match. Wozniacki took a chances and got back level, going into the tiebreaker with momentum.
Clijsters had never lost any of her eight previous tiebreakers at Melbourne Park, and she hit a backhand down the line to take a 5-4 lead. She set up double match point with a crosscourt forehand winner and sealed it with a volley.