Kerber and Wozniacki advance

Reuters

Angelique Kerber

Indian Wells, California - Top seed Victoria Azarenka of Belarus and seventh-seeded Australian Samantha Stosur both withdrew from their quarterfinal matches at the BNP Paribas Open on Thursday because of leg injuries.

Australian Open champion Azarenka pulled out with a right ankle injury after Stosur had exited with a calf injury, handing walkovers for Angelique Kerber and Caroline Wozniacki into the semifinals.

Azarenka, who demolished Russian Maria Sharapova 6-2, 6-3 in last year's final, had complained about her ankle earlier in the week and she limped as she made her way toward the players' dining area before her premature exit was announced.

The Belarusian's departure gifted eighth-seeded Dane Wozniacki, the 2011 champion here, a place in the last four for a third time at Indian Wells.

Earlier in the day, Stosur pulled out after injuring her right calf on Tuesday while serving for the match during her 4-6, 6-2, 6-3 victory over Germany's Mona Barthel in the fourth round.

“I don't know if you can get any more unlucky than that,” Stosur said in a statement. “I think we only played another four points in that match. I felt something go in my calf and it was hurting a fair bit.

“Yesterday I took the day off practice and only did treatment, probably iced it about 10 times. This morning I thought I would give it a shot and tried to go out and warm up.

“After about five minutes, I knew that there was no chance I could play unfortunately. I think this is only the second time I've ever pulled out of a match in my career.”

The other semi-final in the elite WTA event at Indian Wells will be contested between second-seeded Russian Maria Sharapova and her compatriot Maria Kirilenko.

Sharapova, the 2006 champion here, advanced with a 7-6, 6-2 victory over sixth-seeded Italian Sara Errani on Wednesday while Kirilenko booked her place in the last four by upsetting fifth-seeded Czech Petra Kvitova 4-6, 6-4, 6-3. - Reuters