By Nation and AFP
The pair was put to the test by Briton Marcus Ellis and Lauren Smith before prevailing 21-16 21-19 to secure a spot in the semi-finals. They will play the last round-robin match against home favourites Zheng Siwei and Huang Yaqiong of China in the battle for the top position of the group.
In women’s doubles, Jongkolphan Kititharakul and Rawinda Prajongjai beat Gabriela Stoeva and Stefanie Stoeva of Bulgaria 21-16 21-18 to stay in contention group B after losing to Lee So-hee and Shin Seung-chan of South Korea 14-21 8-21 in the first match.
However, Thai singles players were far from success in their second round-robin matches. Ratchanok Intanon lost her steams in the third game and went down to 2017 world champion Nozomi Okuhara of Japan 21-14 11-21 14-21.
In men’s singles group B, Kantaphon Wangcharoen suffered his second straight defeat as he was outclassed by reigning world champion Kento Momota of Japan 18-21 6-21. The Thai No 2 was knocked out of the competition despite having one more match remaining.
India's P.V. Sindhu pulled off a shock at the badminton World Tour Finals on Thursday as she fought back to defeat top-ranked Tai Tzu-ying for the first time in over two years.
Sindhu sank to her knees at the end of an exhausting 14-21, 21-16, 21-18 victory over the Taiwanese in 62 enthralling minutes in the southern Chinese city of Guangzhou.
The 23-year-old, a silver medallist at the Rio Olympics in 2016, faces Zhang Beiwen of the United States on Friday looking to make it three wins out of three in Group A of the $1.5 million end-of-year showpiece.
"Each point was hard fought," said a relieved Sindhu, ranked sixth in the world.
"There were long rallies with good strokes. She was very deceptive and I had to be ready for her strokes.
"Even though I was trailing in the third game I didn't lose hope and I kept fighting."
It was a disappointing day for Taiwan as men's world number three Chou Tien-chen also lost.
Chou was on the end of an 18-21, 21-11, 21-14 defeat to South Korea's buoyant Son Wan-ho.
There was no such trouble for men's number one and world champion Kento Momota of Japan.
He is in ominous form as he looks to put the seal on a breakthrough year and swatted aside Thailand's Kantaphon Wangcharoen 21-15, 21-7 for a second win in a row.
China's Shi Yuqi, one of the main threats to red-hot Momota in the men's draw, dismissed Anthony Sinisuka Ginting of Indonesia, 21-8, 21-19 in 37 minutes.