Sania Mirza [Images] entered the third round of the women's doubles but had to face defeat in the opening round of the mixed doubles at the US Open on Sunday.

Sania, teaming up with, Liezel Huber of South Africa [Images] beat France's [Images] Stephanie Cohen-Aloro and Maria Jose Martinez Sanchez of Spain 6-0, 6-3 in the second round while the Indian teenager and Czech Pavel Vizner went down 2-6, 6-3, 7-10 to the sixth seeded pair of Katarina Srebotnik and Nenad Zimonjic.

Leander Paes [Images] and Czech Martin Damm beat the Austrian-German pair of Alexander Peya and Bjorn Phau 6-3, 7-6 (7/4) to enter the third round of the men's doubles event.

The sixth seeded pair of Paes and Damm will now take on the 11th seeded Austrian duo of Julian Knowle and Jurgen Melzer.

Paes and Damm were in fine form in the opening set and gave away little but the duo struggled in the next set, which was decided through tie-break.

The sixth seeds were pushed hard by their unheralded rivals but Paes and Damm overcame the jitters to seal the issue in their favour in the tie-breaker.

Meanwhile, in the boys' singles competition, which started on Sunday, sixth seeded Sanam Singh made shocking first round exit losing 1-6,1-6 to unheralded Canadian Yoann Re.

More disappointment was in store for Indians as Rupesh Roy blew away a set's advantage to lose 6-4, 5-7, 0-6 to Portugal's Gastao Elias in another first round boys' singles match.

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