Kuala Lumpur: Star Indian shuttler P V Sindhu had to dig deep to beat Denmark's Line Christophersen in the women's singles opening round, while H S Prannoy dished out a superlative display to stun world No. 6 Tien Chen Chou of Chinese Taipei in men's singles at the Malaysia Masters here on Wednesday.
Sindhu, seeded sixth, had to toil for one hour and two minutes to get the better of Christophersen 21-13, 17-21, 21-18 and maintain her superiority over the world No. 33 Dane, who she had defeated four times earlier.
The two-time Olympic medallist, ranked 13th in the world, will next play Japan's Aya Ohori.
World No. 9 Prannoy, later, held his nerve after going a game down to upset Chou, ranked sixth, 16-21, 21-14, 21-13 in his opening match to enter the pre-quarterfinals.
Prannoy will next lock horns with Shi Feng Li of China.
The other Indian man to enter the second round was Kidambi Srikanth, who defeated Toma Junior Popov of France 21-12, 21-16.
He will be next up against Thailand's Kunlavut Vitidsarn, seeded eighth.
However, it was curtains for qualifier Ashmita Chaliha, Aakarshi Kashyap and Malvika Bansod in the women's singles competition as they suffered straight-game defeats to crash out in the opening round.
While Ashmita lost 17-21, 7-21 to fourth seed Yue Han of China, Aakarshi was shown the door by top seed Japanese Akane Yamaguchi 17-21,12-21.
Malvika was no match for second seed Zhi Yi Wang of China as she lost 11-21,13-21.