CHARLESTON, South Carolina (Reuters) - Top seed Caroline Wozniacki of Denmark moved into the quarter-finals at the Family Circle Cup with a 6-2 7-5 win over Switzerland's Patty Schnyder on Thursday.

The 19-year-old Dane, who lost in last year's final, will now play Russia's Nadia Petrova, the 2006 winner who earlier eased past Canada's Aleksandra Wozniak 6-2 6-4.

The Serb now faces eighth-seed Daniela Hantuchova of Slovakia who needed two hours 44 minutes to overcome German Angelique Kerber 6-7 7-5 6-3.

Russia's number seven seed Vera Zvonareva also moved into the third round after cruising past Ukraine's ninth-seeded Alona Bondarenko 6-2 6-1 in just an hour.

(Writing by Frank Pingue in Toronto; editing by Ken Ferris)