Defending champion Daniela round winners Thursday at the Pattaya Open.

The third-seeded Hantuchova notched a 6-3, 6-2 victory over Poland's Urszula Radwanska and will next face the eighth-seeded King in the quarterfinals. King eased past Russia's Alla Kudryavtseva, 6-1, 6-3.

Hantuchova has now reached the quarterfinals for the third time in four events this year. She lost to Kaia Kanepi in the final at the season-opening Brisbane International and was a quarterfinal loser to Petra Kvitova the following week in Sydney before a third-round loss to Kim Clijsters at the Australian Open.

On the way to the Brisbane final, Hantuchova knocked off King in the second round and is now 6-0 all-time against the 23-year-old Florida resident. King, whose lone WTA title came in Thailand at the Bangkok event in 2006, last reached a quarterfinal last September in Seoul.

India's Sania Mirza, the 2009 Pattaya Open runner-up, also moved into the quarters with a 6-4, 7-5 triumph over Britain's Anne Keothavong and will next take on Taiwanese qualifier Su-Wei Hsieh, who knocked off Japanese veteran Kimiko Date-Krumm, 7-5, 6-0.

Friday's other quarterfinal matchups will pit top-seeded Vera Zvonareva, the Pattaya champ in 2009 and 2010, against seventh-seeded Sorana Cirstea and fourth-seeded Russian Maria Kirilenko against crowd favorite Tamarine Tanasugarn of Thailand, the Pattaya runner-up in 1996 and last year.

The 2012 champion will collect $37,000.