Kunlavut Vitidsarn stayed on course to win his first Asian title after reaching the semi-finals of the Badminton Asia Championships in Ningbo, China, on Friday.
Kunlavut battled past Kenta Nishimoto of Japan 21-12, 13-21, 23-21 in an hour and 28 minutes to book his berth in the last four of the men's singles event.
Kunlavut, the world champion and Olympic silver medallist, will face either top seed Shi Yuqi of China or eighth seed Loh Kean Yew of Singapore for a place in the final, as the third seed is bidding to become the first Thai to win the Asian men's singles crown.
Kunlavut is the only Thai player left in the tournament after women's singles hope Supanida Katethong bowed out in the quarter-finals at the Ningbo Olympic Sports Centre Gymnasium on Friday.
The Thai seventh seed lost to second seed Han Yue of China 13-21, 9-21 in just 32 minutes.
Men's doubles players Dechapol Puavaranukroh and Kittinupong Kedren lost to the world No.2 pair and tournament top seeds Goh Sze Fei and Nur Izzuddin of Malaysia 18-21, 20-22 in the last 16 on Thursday.
In other results, fourth seed Li Shifeng of China reached the semi-finals with a 23-21, 21-10 win over fifth seed Kodai Naraoka of Japan. Li will meet compatriot Lu Guangzu in the last four after the unseeded player upset second seed Jonatan Christie of Indonesia 21-13, 21-13.