Former world No.1 Caroline Wozniacki overcame Poland’s Urszula Radwanska in straight sets on Tuesday to reach the second round of the WTA indoor hardcourt event, but Australia’s Anastasia Rodionova was an early casualty.

The 21-year-old two-time defending champion was down a break in the first set before rallying to force the tiebreaker. She then broke three times in the second to clinch victory 7-6 (7-4) 6-2 in just over two hours.

The sixth-ranked Wozniacki will next play Pauline Parmentier of France, who ousted Anna Chakvetadze of Russia 7-5 6-1.

Fourth-seeded Monica Niculescu of Romania also advanced, beating Valeria Savinykh of Russia 6-2 6-2, while No.5 Kaia Kanepi of Estonia ousted Rodionova 6-3 6-4.

Second-seeded Angelique Kerber of Germany also won through, beating Stephanie Foretz Gacon of France 4-6 6-2 7-5.

Alize Cornet of France had the easiest win of the day, routing Danish wildcard Malou Ejdesgaard 6-0 6-0.

Seventh-seeded Ksenia Pervak of Kazakhstan had to retire from her match against Australia’s Johanna Konta when trailing 6-3 1-0.

Sixth-seeded Mona Barthel of Germany defeated Sweden’s Johanna Larsson 6-3 6-4 while, in a bad day for the Swedes, No.8 Sofia Arvidsson lost 7-5 5-7 6-1 to Austria’s Patricia Mayr-Achleitner.

In other first-round matches, Petra Martic of Croatia beat Germany’s Annika Beck 6-4 6-4 and Anne Keothavong of Britain downed Hungary’s Melinda Czink 4-6 6-2 6-3.