Top seed Caroline Wozniacki is out of the Rogers Cup following a defeat to Roberta Vinci . `` It was very difficult with the wind but also French Open winner Li Na and Wimbledon winner Petra Kvitova win their 2nd rd matches . Maria Sanchez , Serena Williams and Vera Wang also advance in star - group event .
Top seed Caroline Wozniacki is out of the Rogers Cup following a defeat to Roberta Vinci . French Open winner Li Na and Wimbledon winner Petra Kvitova win their 2nd rd matches . Maria Sanchez , Serena Williams and Vera Wang also advance in star - group event .