Women's doubles duo Jongkolphan Kititharakul and Rawinda Prajongjai claimed probably the biggest win of their career when they upset Chinese world No.1 Chen Qingchen and Jia Yifang 21-19, 21-15 in the quarter-finals of the Indonesia Open on Friday.
It is the Thais' first victory over Chen and Jia, who have won the world title twice and were runners-up at last year's Olympics, in 13 meetings.
Jongkolphan and Rawinda are the only Thais remaining in the US$1.2 million event in Jakarta.
The seventh-seeded Thai pair will meet sixth seeds Nami Matsuyama and Chiharu Shida in Saturday's semi-finals of the BWF World Tour Super 1000 tournament.
The Japanese duo defeated China's Du Yue and Li Wenmei 21-10, 13-21, 21-9 in the last eight.
Jongkolphan and Rawinda have previously reached the final of a Super 1000 event only once at the Thailand Open in 2020 when they lost to Indonesia's Greysia Polii and Apriyani Rahayu.
In Saturday's other semi-final, Japanese fourth seeds Yuki Fukushima and Sayaka Horota take on South Korea's second seeds Lee So-Hee and Shin Seung-Chan.
There were also major upsets in the women's singles quarter-finals yesterday.
Unseeded Chinese Wang Zhiyi beat top seed Akane Yamaguchi of Japan 21-19, 21-14. Wang will next face compatriot He Bingjiao who stunned third seed An Se-Young of South Korea 15-21, 21-17, 21-14.
Olympic champion and fourth seed Chen Yufei of China cruised past sixth seed Nazomi Okuhara of Japan 21-16, 21-10.
On Thursday night, Thailand's Ratchanok Intanon suffered a shock 21-15, 16-21, 20-22 loss to Denmark's Line Hojmark Kjaersfeldt.