Sania Mirza-Cara Black in US Open semifinal

NEW YORK: Indian tennis ace Sania Mirza and her Zimbabwean partner Cara Black hardly broke a sweat as they entered the US Open women's doubles semifinals after their rivals retired midway through the quarterfinal match here.

Sania and Cara, seeded third, defeated the Kazakh-Chinese pairing of Zarina Diyas and Yi-Fan Xu 6-1 1-0 (retd) in 45 minutes to make the last four stage.

They will now face the Swiss-Italian team of Martina Hingis and Flavia Pennetta. Hingis and Pennetta upstaged fifth seeds Kveta Peschke and Katarina Srebotnik 6-4 6-3 in their last-eight match.

In a match which looked lopsided from the very start, Sania and Cara held serve and broke their rivals twice to pocket the opening set easily before the proceedings came to an end in the opening five minutes of the second set.

In the junior competition, India's Sumit Nagal lost 2-6 2-6 to seventh seeded Korean Duckhee Lee to bow out of the competition.