Petkovic out of Australian Open with back injury



MELBOURNE, Australia (AP) — Andrea Petkovic of Germany has withdrawn from the Australian Open with a stress fracture in her lower back.

Petkovic, ranked No. 10, lost 7-5, 6-4 to Agnieszka Radwanska of Poland in a second-round match at the Sydney International on Tuesday.

The 24-year-old Petkovic was seeded 10th at the Australian Open, which begins Monday at Melbourne Park.