US Open champion Samantha Stosur of Australia advanced to the third round of the Dubai Tennis Championships Wednesday by defeating Lucie Safarova of the Czech Republic 6-1, 6-7 (5), 6-1. Caroline Wozniacki also advanced Wednesday after the third-seeded Danish player opened her title defense by beating Romania's Simona Halep 6-2, 6-3. Earlier, top-ranked Victoria Azarenka pulled out of the tournament because of a left ankle injury. The fourth-seeded Stosur will meet eight-seeded Jelena Jankovic of Serbia in the third round on Thursday. Jankovic defeated Italy's Flavia Pennetta 7-5, 6-4. Wozniacki will face Ana Ivanovic after the Serbian player defeated Maria Kirilenko of Russia, 6-2, 7-6 (4). The ninth-seeded Sabine Lisicki of Germany also advanced after defeating Iveta Benesova of the Czech Republic 6-3, 6-3. Lisicki will play Agnieszka Radwanska in the third round, after the fifth-seeded Polish player defeated Israel's Shahar Peer 7-5, 6-4. Seeds beaten In Monterry, Mexico, fourth-seeded Alexandra Dulgheru of Romania and No. 7-seeded Mathilde Johansson of France were knocked out of the first round of the Monterrery Open Tuesday. Dulgheru was beaten by Silvia Soler-Espinosa of Spain 6-3, 6-3, while Mathilde Jonansson lost to Mandy Minella of Luxembourg 6-1, 5-7, 7-6 (5). No. 6-seeded Greta Arn of Hungary beat Zhang Shuai of China 6-1, 6-4, and eighth-seeded Lourdes Dominguez Lino of Spain defeated Monica Puig of Puerto Rico 6-3, 6-3. Other first-round winners included Frenchwoman Alize Cornet, Maria Abramovic of Croatia, Yaroslava Shvedova of Kazakhstan, Valeria Savinykh of Russia and Hungary's Timea Babos.