Shanghai: India’s P.V. Sindhu pulled off a shock at the badminton World Tour Finals on Thursday as she defeated top-ranked Tai Tzu-ying of Taiwan in three thrilling games.

Sindhu sank to her knees at the end of an exhausting 14-21, 21-16, 21-18 victory in 61 enthralling minutes in the 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.

It was a disappointing day for Taiwan. As well as Tai going down to the sixth-ranked Sindhu, men’s world No. 3 Chou Tien-chen also lost, this time in the men’s draw.

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 No. 1 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, was even more emphatic in dismissing Anthony Sinisuka Ginting of Indonesia, 21-8, 21-19 in 37 minutes.

The top two players from the two groups will qualify for the semi-finals, after which a knockout draw will be held.

The BWF World Tour Finals is one of badminton’s most prestigious tournaments and the year’s biggest event in terms of prize money $1.5 million.