Easy start for Serena

Serena Williams began the defence of her WTA Italian Open crown with a straight sets second round win over Andrea Petkovic on Wednesday.

The 17-time Grand Slam champion and top seed had been suffering from an injured left thigh going into the tournament but was fit enough to play and cruised past her German opponent 6-2 6-2.

US player Varvara Lepchenko upset compatriot and 16th seed Sloane Stephens 6-2 6-2 - the only seed to fall on Wednesday.

Third seed Agnieszka Radwanska beat Argentina's Paula Ormaechea 6-3 6-2, while fourth seed Simona Halep had to come from behind to overcome US player Madison Keys 5-7 6-0 6-1.

Italian tenth seed Sara Errani beat Russian Ekaterina Makarova 6-2 6-3 and Spanish 13th seed Carla Suarez Navarro beat Serena's sister Venus 6-4 6-2.

Another Italian Francesca Schiavone made it into the third round with a 3-6 6-1 7-6(5) victory over Garbine Muguruza Blanco of Spain but home favourite Camila Giorgi, who had upset ninth seed Dominika Cibulkova in the first round, went down 1-6 6-3 6-1 to US player Christina Mchale.

Australian ace Samantha Stosur beat Elena Vesnina of Russia 6-2 6-3 to also progress through.