STUTTGART, Germany (AP) -- Andrea Petkovic of Germany will miss the next three months after tearing ligaments in her right ankle at the Porsche Grand Prix.

Petkovic says a scan confirmed the injury on Friday. She twisted her ankle in Thursday's match against top-ranked Victoria Azarenka in the second round.

Petkovic entered her first tournament since January ranked No. 12. She had been sidelined with a lower back injury.

She also has been nursing a right knee injury.

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