India's Sania Mirzau00a0 lost in straight sets to her doubles partner Elena Vesnina of Russia 6-4, 6-3 in the first round of the ATP-WTA Madrid Masters here yesterday.

Meanwhile, top seed Caroline Wozniacki began her campaign with a 6-2, 6-3 defeat of Japan's Ayumi Morita while two Grand Slam champions, Maria Sharapova and Francesca Schiavone also went through.

French Open champion Francesca Schiavone won her first claycourt match of the season, defeating China's Peng Shuai 7-5, 7-6 (7/2) to reach the second round.

Eighth seed Maria Sharapova struggled in her first clay contest of the season, with the three-time Grand Slam champion coming through for a defeat of Alexandra Rus of the Netherlands 2-6, 6-3, 6-2.