Unseeded Napaporn handed the first set on a platter to Britain's Sarah Coles 1-6 before launching a comeback to take the next two sets 7-5 7-6 (7-2) in the second round.

The Thai also had to shrug off a sluggish start in her first-round match against second-seeded Vilmarie Castellvi before prevailing 1-6 6-3 7-6 (7-4).

"I played very bad today. I could not find the momentum. But somehow I tried to fight for every point and was lucky to win the crucial ones," said Napaporn, the only Thai remaining in the event.

Currently ranked 254 in the world, Napaporn needs to accumulate as many points as possible to get a chance to compete in the US Open qualifying. Her next opponent is American-Indian Sunitha Rao, a 6-4 7-5 winner over American Riza Zalamedas.

"It will be a tough match. But if I can get the momentum going I think I can beat her," she said.

Meanwhile in Bangkok, the last Thai hopes - Nudnida Luangnam and Wilawan Choptang - were eliminated from the quarter-finals of the $10,000 PTT Bangkok Open Circuit I at the Rama Gardens Hotel yesterday.

Top seed Nudnida was upset by Indonesia's Ayu-Fani Damayanti 4-6 (7-1) 6-3 and Wilawan fell to Uzbek Dilyara Saidkhodjaeva 6-4 6-3. In the other matches, seventh-seeded Chan Wing-Yau Venise of Hong Kong defeated countrywoman Lam Po-Kuen 6-3 6-4, and South Korea's Lee Jin-a beat Marinne Giraud of Mauritius 6-3 6-3.