Badminton: Boonsak and Li into Li-Ning Singapore Open semis, but Nehwal crashes

Thailand's Boonsak Ponsana stayed on course to retain his men's singles title at the Li-Ning Singapore Open when he defeated Malaysia's Chong Wei Feng 21-10, 21-19 in the quarter-finals on Friday.

The 31-year-old, back to a career-best world ranking of No. 4, will play either Takuma Ueda or Kento Momota of Japan in the semi-finals on Saturday.

In the women's singles, world No. 1 Li Xuerui also booked a berth in the last four when she dispatched Thailand's Sapsiree Taerattanachai 21-11, 21-19.

She will play team-mate Sun Yu, who upset Tai Tzu-ying of Chinese Taipei 21-19, 21-18.

However, world No. 4 Saina Nehwal of India was upset by Indonesia's Lindaweni Fanetri, losing 21-17, 13-21, 13-21.

The second-seeded Indian said: "I've been playing many tough matches consecutively so I felt very tired. I didn't have the stamina to take it through three games."