Fourth-seeded Australian Samantha Stosur has advanced to the third round of the Dubai Tennis Championships by defeating Lucie Safarova of the Czech Republic 6-1, 6-7 (5), 6-1.

The US Open champion broke twice in both the first and third sets.

Stosur saved all nine break points she faced in the match on Wednesday.

Earlier in the day, top-ranked Victoria Azarenka pulled out of the Dubai tournament because of a left ankle injury.

The Australia Open champion, who has won 17 straight matches so far this season, says she will rest for two or three days.

Later in the day, Caroline Wozniacki is scheduled to open her title defence against Simona Halep of Romania.