India Open: World No. 1 An Se Young out after aggravating knee injury; Tai Tzu, Wang Zhi win

New Delhi: World No. 1 and defending champion An Se Young of Korea retired hurt against Singapore's Jia Min Yeo after aggravating her knee injury in women's singles quarterfinals at India Open super 750 badminton tournament here on Friday.

The 21-year-old Young, who had hurt her knee during the Asian Games last October, was trailing 19-21 0-3 against Jia Min, when she decided to throw in the towel.

The world No. 20 Singaporean thus recorded only her second win against Young, who had made a good start to the season with a title winning run at Malaysia Open Super 1000 last week.

"I knew the injury could get worse but I wanted to play more matches ahead of the Olympics,' she said.

Jia Min was happy to execute her plan but acknowledged that her opponent was not at her best shape.

"I think I had to be fast on the court and make less error, try to not lose my focus and I am happy I won the first game but she was not running her best due to her physical condition. Hope she comes back strong in next tournament," Jia Min said.

Jia Min will next face former world no 1 Tai Tzu Ying, who beat China's sixth seed He Bing Jiao 21-12 21-12.

World No.10 Wang Zhi Yi of China recorded a 22-20, 21-8 win against Thailand's Busanan Ongbamrungphan in another women's singles quarter-finals.

In men's singles, World No.18 Lee Cheuk Yiu of Hong Kong stunned Tokyo Olympic bronze medallist Anthony Sinisuka Ginting 21-17 18-21 21-13. He will face World Championships silver medallist Japanese Kodai Naraoka, who notched a 13-21 21-9 21-16 win over Malaysia's Lee Zii Jia.

"Lee was so quick with the smash, so I picked up the pace focusing on the smash," Naraoka said.

"From now on, the race will continue for sure, however, I want to pay attention to the ongoing match."

In mixed doubles, Thailand's Dechapol Puavaranukroh and Sapsiree Taerattanchai upset defending champions Yuta Watanabe and Arisa Higashino of Japan 21-17 15-21 27-25 in their quarterfinal.

Among others, Korean pair of Kim Won Ho and Jeong Na Eun, Chinese duo of Jiang Zhen Bang and Wei Ya Xin entered the semifinals in mixed doubles.