Toronto: World number one Caroline Wozniacki headlined the parade of seeded players to fall at the Toronto Cup with a shock loss on Wednesday while Maria Sharapova and Serena Williams moved into the last 16.

Defending champ Wozniacki rarely looked comfortable on court and did not live up to her top seeding with seven double faults and a slew of errors during a 6-4, 7-5 loss to Italy's Roberta Vinci in windy conditions that played havoc with her game.

Injury

A day after second seed Kim Clijsters dealt the tournament a blow by retiring from her opening match with a partial tear of a stomach muscle, it was Wozniacki's turn for a premature exit.

"I didn't get a chance to really get any rhythm, it was difficult first with the wind but also the way that she was playing," Wozniacki, who became the seventh seeded player to exit the tournament in Toronto this week, told reporters.

Results

Second round (prefix number denotes seeding): 4-Victoria Azarenka (Belarus) beat Stephanie Dubois (Canada) 6-0 6-0; 5-Maria Sharapova (Russia) beat Bojana Jovanovski (Serbia) 6-1 7-5; 3-Vera Zvonareva (Russia) beat Nadia Petrova (Russia) 7-5 6-4; Ana Ivanovic (Serbia) beat Iveta Benesova (Czech Republic) 6-3 6-2; 11-Andrea Petkovic (Germany) beat Greta Arn (Hungary) 6-4 7-5; Serena Williams (U.S.) beat Julia Goerges (Germany) 6-1 7-6(7); Flavia Pennetta (Italy) beat Galina Voskoboeva (Kazakhstan) 6-2 3-6 2-6; 6-Li Na (China) beat Peng Shuai (China) Walkover; 10-Samantha Stosur (Australia) beat Aleksandra Wozniak (Canada) 6-3 6-4; Roberta Vinci (Italy) beat 1-Caroline Wozniacki (Denmark) 6-4 7-5; 13-Agnieszka Radwanska (Poland) beat Petra Martic (Croatia) 6-3 6-3; Maria Jose Martinez Sanchez (Spain) beat Daniela Hantuchova (Slovakia) 7-5 6-2; Lucie Safarova (Czech Republic) beat Simona Halep (Romania) 6-2 6-4; 7-Petra Kvitova (Czech Republic) beat Anabel Medina Garrigues (Spain) 7-6(3) 6-3; 8-Francesca Schiavone (Italy) beat Ekaterina Makarova (Russia) 6-1 6-3.