Kunlavut Vitidsarn kept alive his bid for back-to-back titles after reaching the quarter-finals of the US750,000 Singapore Open on Thursday.
The world No.3 was joined by Supanida Katethong and mixed doubles pair Supak Jomkoh and Supissara Paewsampran in the quarter-finals.
Seventh seed Kunlavut, who won the Thailand Open on Sunday, survived a tough test against Ng Tze Yong as he overcame the Malaysian 21-18, 22-24, 21-13.
The 22-year-old will play Christo Popov of France for a place in the semi-finals of the World Tour Super 750 event.
In the women's singles, Supanida rallied to stun sixth seed Carolina Marin of Spain 17-21, 21-19, 21-17 and will meet Olympic champion Chen Yufei of China in the last eight.
In the mixed doubles, Supak and Supissara eased past Thom Gicquel and Delphine Delrue of France 21-12, 23-21.
All the other Thai players bowed out on Thursday, including women's singles star Ratchanok Intanon, mixed doubles duo Dechapol Puavaranukroh and Sapsiree Taerattanachai, women's doubles pairs Jongkolphan Kititharakul and Rawinda Prajongjai and Aimsaard sisters -- Benyapa and Nuntakarn.
Ratchanok went down to Aya Ohori of Japan 16-21, 10-21 while Dechapol and Sapsiree lost to Denmark's Mathias Christiansen and Alexandra Boje 24-26, 20-22.
Jongkolphan and Rawinda were beaten by second seeds Nami Matsuyama and Chiharu Shida of Japan 21-17, 14-21, 16-21 and Benyapa and Nuntakarn lost to Chinese top seeds Chen Qingchen and Jia Yifan 7-21, 13-21.
In other results, women's singles top seed Akane Yamaguchi of Japan beat Michelle Li of Canada 21-12, 21-19 and second seed An Se-Young, the Thailand Open champion, defeated Yeo Jia Min of Singapore 21-12, 21-11.
