Mixed doubles pair Dechapol Puavaranukroh and Sapsiree Taerattanachai bowed out in the quarter-finals of the season-opening BWF Malaysia Open in Kuala Lumpur on Friday.
The loss meant there's no Thai player left in the US$1.3 million BWF World Tour Super 1000 event in the Malaysian capital.
Sixth seeds Dechapol and Sapsiree were beaten by Hee Yong Kai and Tan Wei Han of Singapore 16-21, 19-21 in 48 minutes.
The Singaporean pair go on to meet seventh seeds Kim Won-Ho and Jeong Na-Eun of South Korea in today's semi-finals.
The Koreans knocked out top seeds Zheng Siwei and Huang Yaqiong of China 21-11, 18-21, 21-17.
In the women's singles event, top seed An Se-Young and second seed Chen Yufei moved into the last four in contrasting fashion.
An needed three games to overcome Yeo Jia Min of Singapore. The Korean dropped the first game but rallied to deny Yeo 16-21, 21-12, 21-19.
Chen, who knocked out Thai hope Ratchanok Intanon in the last 16, cruised past seventh seed Gregoria Tunjung of Indonesia 21-13, 21-17.
Fourth seed Tai Tzu-ying of Taiwan also made it to the last four after she beat sixth seed He Bingjiao of China 21-16, 21-15.
Akane Yamaguchi's comeback ended yesterday after the Japanese third seed lost to Zhang Yiman of China 12-21, 21-17, 21-17.
Yamaguchi was back in action for the first time after being injured at the Asian Games in Hangzhou, China, in September last year.
An will take on Zhang while Tai and Chen will square off in today's semis.
In the men's singles event, Lin Chun-yi of Taiwan continued his amazing run after knocking out third seed Li Shifeng of China.
A day after upsetting Thai world champion and fifth seed Kunlavut Vitidsarn in the last 16, the Taiwanese claimed another surprise result, beating Li in two games 21-12, 21-18.
He will play Denmark's Anders Antonsen, who knocked out second seed Kodai Naraoka of Japan 16-21, 21-12, 21-7, in the semis.