
The world No 14 stunned the Taiwanese 21-19 8-21 21-17, ending her losing streak to the top seed who entered the match with a 7-0 head-to-head record over the Thai.
Since losing a match to Sung Ji Hyun of South Korea in the preliminary round of the Superseries Finals in Dubai last December, Tai never lost to anyone before Friday. She has won four titles: All England, Malaysia Open, Singapore Open and Asian Championships.
Nitchaon next faces Sayaka Sato of Japan, the world No 17 who is tied with the Thai at 2-2 in their previous encounters.
However, no other Thais advanced to the semi-final stage. Anggia Shitta Awanda and Ni Ketut Istrarani of Indonesia beat Puittita Supajirakul and Sapsiree Taerattanachai 13-21 21-19 21-11 in the women’s doubles quarter-finals.
In men’s doubles, Dechapol Puavaranukroh and Kittinupong Kerden went down to Fajar Alfian and Muhammad Adrianto of Indonesia 13-21 21-18 12-21.