Updated

Former champion Caroline Wozniacki secured a quarterfinal berth without lifting her racquet Thursday at the Family Circle Cup tennis event.

The second-seeded former world No. 1 star was scheduled to meet Andrea Petkovic on Day 4, but the oft-injured former top-10 German pulled out of the draw due to a calf injury.

Wozniacki, a runner-up at Indian Wells a few weeks ago, titled on the green clay here at Daniel Island Tennis Center in 2011 and was the runner-up back in 2009.

The winner of this $795,000 tournament will earn $125,000.