Fourth-seeded Ratchanok battled back after dropping the opening game to beat old foe Sung Ji-Hyun of South Korea 19-21, 24-22, 21-17.
She faces a tough match against Indian sixth seed Pusarla V Sindhu in today’s quarter-finals after the Indian star cruised past Kisona Selvaduray of Malaysia 21-10, 21-12.
“I think Sung [Ji-Hyun] had prepared very well for this match and tried to control the game from the beginning. She played like An Se-Young who beat me last week in the Yonex Thailand Open quarter-finals,” said Ratchanok in the post-match interview.
“I tried to have better control in the second and third games and adapted my game as I played which fortunately worked.”
Pornpawee beat fellow Thai Benyapa Aimsaard 21-18, 21-14 and will play seventh seed An Se-Young of South Korea in today’s quarter-finals.
An defeated Yeo Jia Min of Singapore 21-15, 21-7.
“I was put on court No.3 for the first time today and felt a bit nervous,” said Pornpawee. “But I tried to focus and concentrate on my game and fortunately was able to execute my game plan.
“I am happy to be able to win today and advance to the next round. My next match against An Se-Young will be tough. She is a very strong player and I will have to do my best to have a chance to beat her.”
Mixed doubles stars Dechapol Puavaranukroh and Sapsiree Taerattanachai, winners of the Yonex Thailand Open on Sunday, also moved into the last eight as did compatriots Supak Jomkoh and Supissara Paewsampran.
Top-seeded Dechapol and Sapsiree defeated Goh Soon Huat and Shevon Jemie Lai of Malaysia 21-12, 21-19 while Supak and Supissara upset seventh seeds Marcus ellis and Lauren Smith of England 21-18, 11-21, 23-21.
“Today, we were able to play the way we wanted to and forced them to make a lot of errors and that’s why we won,” said Sapsiree.
“We wanted to be aggressive from the beginning and we did that today,” added Dechapol.
Jongkolphan Kititharakul and Rawinda Prajongjai, runners-up at the Yonex Thailand Open, also reached the women’s doubles quarter-finals after they beat Amalie Magelund and Freja Ravn of Denmark 21-17, 21-15.
“I think we played a good match today. We never played them before and were a bit surprised how well they did,” said Jongkolphan. “The first game was quite close but fortunately we were able to improve in the second game.”
There is no Thai player left in the men’s singles event after Kunlavut Vitidsarn lost to Danish fourth seed Viktor Axelsen, winner of the Yonex Thailand Open on Sunday, 11-21, 13-21.
Women’s top seed Tai Tzu-ying of Taiwan progressed to the quarter-finals with a 22-20, 21-16 win over Gregoria Mariska Tunjung of Indonesia.
She will play eighth seed Michelle Li of Canada in today’s quarters.
Fifth seed Carolina Marin, winner of the Yonex Thailand Open, also advanced after beating Line Hojmark Kjaersfeldt of Denmark 21-19, 21-16.
In the men’s singles event, second seed Chou Tien-chen of Taiwan moved into the last eight following his 21-19, 21-16 win over Brice Leverdez of France.
Sameer Verma of India joined Chou in the last eight after beating Rasmus Gemke of Denmark 21-12, 21-9.
Two men’s seeds - No.5 Anthony Ginting of Indonesia and No.7 Angus Ng Ka Long of Hong Kong - crashed out yesterday. Ginting lost to Lee Cheuk Yiu of Hong Kong 19-21, 21-13, 12-21 while Long fell to Wang Tzu-wei of Taiwan 13-21, 11-21.