Thailand's Kunlavut Vitidsarn defeated France's Toma Junior Popov 2-1 to reach the semi-finals of the BWF World Tour Finals in Bali on Friday.
The 20-year-old finished off the Frenchman 21-12, 20-22, 21-5 in their last Group B match in the men's singles of the season finale.
Group B runner-up Kunlavut advanced to the last four along with group winner Lee Zii Jia of Malaysia.
Denmark's Viktor Axelsen and India's Lakshya Sen progressed to the semi-finals from Group A.
Women's singles star Pornpawee Chochuwong and mixed doubles duo Dechapol Puavaranukroh and Sapsiree Taerattanachai are the other Thais in Saturday's semi-finals.
Pornpawee defeated India's PV Sindhu 21-12, 19-21, 21-14 for her third successive win in Group A yesterday with both advancing to the last four.
In Group B, Thailand's Busanan Ongbamrungphan was eliminated after losing to Japan's Akane Yamaguchi 21-18, 21-18.
Dechapol and Sapsiree beat England's Marcus Ellis and Lauren Smith 21-18, 21-13 for a perfect 3-0 record in the group stage.
The defending champions Thais are chasing their fourth straight title and a hat-trick of wins in three consecutive weeks in Bali.
Players of season
Denmark's Axelsen and Taiwan's Tai Tzu-ying have been named the BWF male and female payer of the year respectively for their feats during the 2020-2021 season, the Badminton World Federation announced yesterday.
Thailand's Kunlavut was named the most promising player.