Roberta Vinci beats Petkovic in 2nd round in St. Petersburg

ST. PETERSBURG, Russia (AP) Defending champion Roberta Vinci advanced to the quarterfinals at the St. Petersburg Ladies Trophy by beating Andrea Petkovic 6-4, 6-4 Thursday.

The sixth-seeded Italian was broken twice in the first set.

Vinci will next face either Australian Open finalist Venus Williams or Kristina Mladenovic.

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