Keothavong lost the first set against the Hungarian qualifier before fighting back to record a 4-6 6-2 6-3 triumph.

The comeback victory was particularly welcome as it was Keothavong's first win on the WTA Tour since Doha in February.

The 28-year-old will next take on either second seed and world number 15 Angelique Kerber of Germany or Frenchwoman Stephanie Foretz Gacon.

Two-time defending champion Caroline Wozniacki also secured her place in round two following a 7-6 (7/4) 6-2 triumph in her first match back on home soil.

The 21-year old Dane was down a break in the first set before rallying to force, and then win, the tie-breaker. She then broke three times in the second to clinch victory in just over two hours.

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