Defending champion Saina Nehwal and two-time World Championship bronze medallist PV Sindhu advanced to the quarterfinals but it turned out to be a dismal day for star shuttlers lin Dan and lee Chong Wei, who crashed out of the India Open Super Series here on Thursday.
Sindhu was a little circumspect during the match and committed a few unforced errors before surpassing Thailand's Busanan Ongbumrungphan 17-21, 21-19, 21-16 in a women's singles match that lasted an hour and 16 minutes here.
She will next take on Korea's Bae Yeon Ju, who beat Japan's Yui Hashimoto 21-16, 21-10 in another match.
later in the day, Saina saw off Nitchaon Jindapol of Thailand 21-19, 21-14 to set up a clash with Korean fifth seed Sung Ji Hyun.
However, the highlight of the day was the stunning losses of two-time silver medallist lee Chong Wei and five-time World Championship lin Dan, considered to be the biggest contenders for the Rio Games gold medal.
While Korea's Son Wan Ho stunned the six-time All England champion lin Dan of China, seeded fourth, 21-13, 22-20, former World no. 1 lee, top seed, suffered a 19-21, 19-21 loss to Hong Kong's Wei Nan, ranked World No 14. Two more top 10 players bite the dust in men's singles at the Siri Fort Sports Complex here.