Kunlavut Vitidsarn moved closer to winning back-to-back titles after securing a semi-final place at the US750,000 Singapore Open on Friday.
The world No.3, who won the Thailand Open last week, beat Christo Popov of France 21-13, 21-17 in the quarter-finals of the World Tour Super 750 event.
The 22-year-old from Chon Buri is seeking his third title of the year as he also won in India earlier this year.
In today's semi-finals, the former three-time world junior champion will face second seed Anthony Ginting of Indonesia or Li Shifeng of China.
Denmark's Anders Antonsen takes on third-seeded Kodai Naraoka of Japan in the other semi-final.
In the quarter-finals, Naraoka defeated China's Shi Yuqi 21-14, 21-16 and Antonsen beat Lee Chia-hao of Taiwan 12-21, 21-13, 21-11.
In the women's singles, top seed Akane Yamaguchi defeated her Japanese compatriot Aya Ohori 21-18, 19-21, 21-16.
In the semi-finals, Yamaguchi will be up against Olympic champion Chen Yufei of China, who beat Thailand's Supanida Katethong 21-18, 21-15.
Second seed An Se-Young of South Korea finished off China's Wang Zhiyi 21-18, 21-18.
An is looking for her second title in a row after her Thailand Open victory.
An will meet third seed Tai Tzu-ying in the last four after the Taiwanese saw off China's He Bingjiao 21-16, 21-11.
In the mixed doubles, Thailand's Supak Jomkoh and Supissara Paewsampran lost to Mathias Christiansen and Alexandra Boje of Denmark 13-21, 21-19, 19-21.