MELBOURNE, Australia (AP) Andrea Petkovic of Germany has withdrawn from the Australian Open with a stress fracture in her lower back.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

Serena Williams could have been beaten by Steffi Graf, suggested former WTA No. 9 Andrea Petkovic recently. According to Petkovic, her German compatriot had one particular weapon in her arsenal ...