India's Subhankar Dey produced the biggest upset of the Yonex-Sunrise India Open so far, knocking out fourth seed Indonesian Tommy Sugiarto, while former champions P V Sindhu and Kidambi Srikanth also progressed to the second round on Wednesday.
Unseeded Subhankar, ranked 44th in the world, eked out a stunning 14-21, 22-20, 21-11 triumph over world number 9 Sugiarto to join a group of Indians, including H S Prannoy, B Sai Praneeth and Sameer Verma, in the men's singles second round.
Earlier, Sindhu, who reached the finals in the last two editions and won the title in 2017, brushed aside fellow Indian Mugdha Agrey 21-8, 21-13 in women's singles, while Srikanth recorded his fourth successive win over Hong Kong's Wong Wing Ki Vincent with a 21-16, 18-21, 21-19 triumph in men's singles.
Prannoy also showed good signs of recovering from a gastro-esophageal reflux disease that troubled him last year, notching up a come-from-behind 14-21, 21-18,21-14 win over Thailand's eighth seeded Kantaphon Wangcharoen.
Fifth seed Sameer Verma beat Denmark's Rasmus Gemke 21-18, 21-12, while Riya Mookerjee shocked Thailand's Phittayaporn Chaiwan 21-17, 21-15 to set up a meeting with Denmark's eighth seed Mia Blichfeldt, who knocked out Rita Thaker.
Swiss Open finalist B Sai Praneeth recovered from a first-game reversal to outwit compatriot Kartikey Gulshan Kumar 22-24, 21-13, 21-8 to also enter the second round.
Former champions Ratchanok Intanon and Li Xuerui made a good start to their respective campaigns. The fourth-seeded Intanon, who is eyeing a third title at this prestigious event, comfortably beat India's Sai Uttejitha Rao Chukka 21-9, 21-6.
London Olympic Gold medallist Xuerui, the winner of this tournament in 2012, overcame a tough opponent in Nitchaon Jindapol with a 21-17, 21-11 win.
Third seed He Bingjiao needed 30 minutes to dismiss India's Prashi Joshi 21-12, 21-15 and was joined by her compatriot Chen Xiaoxin following her 21-15, 21-11 victory over Yulia Yosephin Susanto.
In doubles, sixth seeds Manu Attri and Sumeeth Reddy blew away younger countrymen Ravi and Lakshay Saroha 21-14, 21-7.
Pranaav Jerry Chopra and Shivam Sharma, who qualified for the main draw, made short work of Senthil Vel Govindarasu and Vembarasan Venkatachalam 21-13, 21-13.
In women's doubles, the pairs of Pooja Dandu-Sanjana Santosh and Venkata Ramya Tulasi Bailupudi-Shivani Santosh Singh made it through Round 2.