Melbourne: French Open champion Li Na moved into the fourth round at the Australian Open on Friday after her opponent Anabel Medina Garrigues withdrew injured.

The Spaniard rolled on her right ankle in the third game of the first set and collapsed to the ground clutching her leg, leaving Li and the crowd on Rod Laver Arena in stunned silence.

The tearful 26th seed received treatment and resumed playing for another game but was clearly hammpered by the injury and retired at 3-0 and 30-0 down.

China's Li, seeded fifth, will next face Kim Clijsters in a rematch of last year's final, which the Belgian won.