MELBOURNE, Australia — Third-seeded Victoria Azarenka reached the Australian Open semifinal, holding her nerve despite trouble with her serve in a 6-7 (7-0), 6-0, 6-2 win over No. 8 Agnieszka Radwanska today.
It was her second win in six Grand Slam quarterfinals. She has never gone further than the semifinals, and next meets defending champion Kim Clijsters, who defeated No. 1-ranked Caroline Wozniacki 6-3, 7-6 (7-4). That ensures that Wozniacki will lose the No. 1 ranking. Clijsters had an early service break in the second set and broke again to lead 4-2.
Azarenka, a 22-year-old Belarusian, extended her winning streak this season to 10 matches, her title at Sydney including a semi win over Radwanska.
"I'm really glad I could stay tough and finish the match," she said. "I'm just really happy to be in the semifinals to give it all out there."
Azarenka lost just 12 games in the first four rounds. But she had six double faults and made 38 unforced errors during her two-hour match against Radwanska.
The first set featured eight service breaks, and there were 15 overall in the match. Azarenka's double fault helped give Radwanska a 6-0 lead in the tiebreaker, followed by a wild errant backhand by Azarenka on set point.
But Azarenka, who can attain the No. 1 ranking by the end of the tournament, won the next seven games.
Five-time champion Serena Williams is already out of the tournament. Her 17-match winning streak at the Australian Open ended in a 6-2, 6-3 loss to No. 56-ranked Ekaterina Makarova.
The margin equaled the biggest Grand Slam defeat of Williams' 17-year career.
Makarova will face three-time major winner Maria Sharapova in an all-Russian quarterfinal.
Sharapova rallied past Sabine Lisicki 3-6, 6-2, 6-3 before defending men's champion Novak Djokovic fended off a resurgent Lleyton Hewitt 6-1, 6-3, 4-6, 6-3.
Next up for Djokovic is fifth-seeded David Ferrer, who had a surprisingly easy 6-4, 6-4, 6-1 win over Richard Gasquet.
Djokovic had won 23 straight sets at Melbourne Park before he suddenly wobbled against Hewitt, a two-time Grand Slam champion who has slipped to No. 181 in the rankings after a series of injuries.
Hewitt, a wild-card entry in his 16th straight Australian Open, rallied from 3-0 down in the third set in front of a raucous home crowd to force a fourth set, but Djokovic gathered his composure.
Kei Nishikori beat sixth-seeded Jo-Wilfried Tsonga 2-6, 6-2, 6-1, 3-6, 6-3 to become the first Japanese man to reach the quarterfinal of the Australian Open since the Open era began in 1968. He next faces Andy Murray.