The 30-minute duel had some exciting moments as the two players fought hard for supremacy with Sindhu conceding a 4-2 lead to Zhang, who could only manage a one-point advantage at the break.
The top seeded Indian duo, who reached the semi-finals of the season-opening Malaysia Open super 1000, was scheduled to face Chinese Taipei's Su Ching Heng and Ye Hong Wei in the opening round.
Saina Nehwal continued to gain in confidence ahead of Olympics as the top-seeded Indian entered the Thailand Open Grand Prix Gold final after outlasting local favourite Porntip Buranaprasertsuk with a straight-game win in Bangkok on Saturday.
An upset stomach ruined her campaign at the World Championship last week, but Saina Nehwal is not too upset at missing the bronze.
A look at the draw and she knew it was not going to be easy but rising shuttler P V Sindhu said she never underestimated herself as she beat one giant after another for a historic bronze medal at the World Championships in Guangzhou, China.
Ace Indian shuttler Saina Nehwal got a shot in the arm ahead of next month's Olympics as she lifted the Thailand Open Grand Prix Gold title after rallying to beat Thailand's Ratchanok Inthanon in the final of the event in Bangkok on Sunday.
Indian pair toiled hard for one hour and 15 minutes to beat their world No 6 Malaysian opponents 18-21, 24-22, 22-20
P V Sindhu's campaign at the Indonesia Open Super 1000 tournament came to an end after she went down to former World champion Ratchanok Inthanon of Thailand in a hard-fought women's singles semi-final, in Bali, on Saturday.
Olympic medallists Saina Nehwal and PV Sindhu sailed into the women's singles quarter-finals with straight-game wins but it was curtains for Kidambi Srikanth at the BWF Badminton World Championships, in Nanjing, China on Thursday.
Olympic silver medallist P V Sindhu continued her unbeaten run while debutant Sameer Verma also qualified for the knockout stage with a straight-game win in his last Group B match at the BWF World Tour Finals.
Former World No 1 Saina, the London Olympics bronze medallist, lost 14-21, 21-17, 17-21 to World No 2 Yamaguchi in a 50-minute women's singles clash.
The World No 6 will next face Spain's Pablo Abian on Wednesday.
Verma who had shocked Malaysia's eighth seed Lee Zii Jia in the opening round, needed just 39 minutes to see off Gemke
Now all eyes are on the two Super 1000 events -- Yonex Thailand Open (January 12-17) and Toyota Thailand Open (January 19-24) as the world's best return to action following a prolonged break.
India's P V Sindhu took a firm step in her quest for Olympic gold in the women's singles badminton, easily disposing off the challenge from Japan's Akane Yamaguchi in the women's singles badminton quarter-final in Tokyo, on Friday, July 30, 2021.
'Her defence was the one only problem. (Carolina) Marin and Pornpawee (Chochuwong) are good attacking players, they were using a lot of half smash and straight smash, and when Sindhu's defence goes down on a day, it affects her other skills as well, she gets nervous. But now she has improved a lot in her defence as well. Her endurance on the court is also good.'
Defending champion P V Sindhu stood just one step away from retaining her title after defeating Thailand's Ratchanok Inthanon in a lop-sided semi-final at the $ 350,000 India Open Super 500 tournament in New Delhi on Saturday.
Srikanth had entered the finals of Commonwealth Games last year but he failed to reach the summit clash in any BWF superseries or BWF World Tour tournament since his French Open win in October, 2017.
Assured of atleast a bronze at the World Badminton Championship, ace shuttler Saina Nehwal described her quarterfinal win as "special" and said patience was the key to her success.
Saina Nehwal made a perfect start to the new season, reaching the women's singles final of the $ 350,000 Indonesia Masters with a thrilling straight-game win over world no 4 Ratchanok Inthanon of Thailand in Jakarta, on Saturday.
H S Prannoy lost in the opening round even as compatriots Saina Nehwal and P V Sindhu entered the second round of the $ 350,000 India Open Super 500 tournament, in New Delhi on Wednesday.
India ace Kidmabi Srikanth clinched his third Super Series Premier title with a dominating straight-game victory over Korean veteran Lee Hyun II in a lop-sided final of the US $750,000 Denmark Open, in Odense, on Sunday.
Olympic silver medallist P V Sindhu progressed to the quarter-finals of the All England Championship with a hard-fought win over Thailand's Nitchaon Jindapol in women's singles, in Birmingham.