Anne Keothavong has exited the Pattaya Open in Thailand, losing her second-round match to Sania Mirza.

Keothavong, who stunned second seed and world number 16 Dominika Cibulkova in round one for the biggest win of her career, was beaten 6-4 7-5 by the Indian.

The 28-year-old Londoner broke her opponent once in each set but Mirza capitalised on Keothavong's meagre 47 per cent of first serves in to break four times in a match which lasted one hour and 39 minutes.

Meanwhile, defending champion Daniela Hantuchova won through to the quarter-finals with a straight-sets win over Urszula Radwanska.

Hantuchova won 6-3 6-2 to book a last-eight meeting with eighth-seeded American Vania King, who easily beat Alla Kudryavtseva 6-1 6-3.

Qualifier Su-wei Hsieh continued her impressive run as she toppled Japanese veteran Kimiko Date-Krumm 7-5 6-0.

The world number 159 will next meet Mirza.

The other quarter-final matches will see top seed Vera Zvonareva meet Sorana Cirstea while local hopeful Tamarine Tanasugarn faces fourth seed Maria Kirilenko.