However, it was curtains for B Sai Praneeth, who went down fighting to Sony Dwi Kuncoro of Indonesia, in his third round men's singles match.
Sindhu, who dropped a place and consequently fell out of the top-10 in the world badminton rankings, faced a tough challenge from Indonesia's Lindaweni Fanetri before prevailing 21-16, 16-21, 21-19 in 65 minutes.
The second seeded Indian initially trailed in the opening game before catching up at 10 and forging ahead 11-10 at the break.
After the break, Sindhu raced away to 16-11, and even though the Indonesian reduced the gap to 16-17, she took the game comfortably.
The unseeded Fanetri, however, stunned Sindhu in the second game as she not only opened up a 7-1 lead but never let the Indian back, taking it to the decider.
In the third game also, the world No.11 Indian was far behind as Fanetri led 11-3 at the break and then extended her lead to 16-6. But just when it seemed all over for Sindhu, the Indian snatched four points on the trot and then added another seven consecutive points to draw level at 17-17. She then her nerve to seal the issue.
In the quarter-finals, Sindhu will take on Li Han of China.
In the men's singles, Prannoy, seeded third, rallied from a game down to register a 17-21, 21-19, 21-14 victory over Lin Yu-Hsien of Chinese Taipei in 56 minutes.
He will face Sony Dwi Kuncoro, who had earlier in the day beaten eighth seeded Praneeth 21-16, 19-21, 21-17.
Image: P V Sindhu
Photograph: Victor Fraile/Getty Images
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