Sindhu, who twice won a bronze medal at the 2013 and 2014 editions, survived a scare against Hong Kong's Cheung Ngan Yi before prevailing 19-21 23-21 21-17 in a thrilling women's singles match that lasted an hour and 27 minutes.
The 22-year-old Indian fought back from 13-16 down in the second game after losing the first to eventually come up trumps. She will face fifth seed Sun Yu of China next.
On a 12-match winning streak, Srikanth knocked out World No. 18 Antonsen 21-14 21-18. The World No. 10 Indian will clash with top seed and World No. 1 Korean Son Wan Ho in the quarterfinals.
"It was a good game today. There were some intense rallies and I am happy for the win," Srikanth told PTI.
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Srikanth, who finished at the pre-quarterfinals in the last two editions, has a 4-4 head-to-head record against Son, whom he has beaten twice this year en route to his titles at Indonesia and Australia in June.
Later in the day, B Sai Praneeth and Ajay Jayaram, however, suffered contrasting defeats to crash out of the tournament.
Praneeth fought hard before going down 21-19 10-21 12-21 to World No. 4 Chou Tien Chen of Chinese Taipei, while Jayaram, who had disposed off The Netherland's Mark Caljouw yesterday, was no match for two-time defending champion Chen Long of China as he lost 11-21 10-21 in 41 minutes.
India's top mixed doubles pair of Pranaav Jerry Chopra and N Sikki Reddy, seeded 15th, played their heart out before going down 22-20 18-21 18-21 to Indonesian World Number 6 duo of Debby Susanto and Praveen Jordan.
Among others, five-time champion Lin Dan, his compatriot Tian Houwei, Viktor Axelsen and Hong Kong's Wong Wing Ki Vincent also were through to the quarters in men's singles.
In women's singles, China's Chen Yufei stunned top seed Akane Yamaguchi to reach the quarters. Thailand's Ratchanok Intanon, two-time champion Carolina Marin, Japan's Nozomi Okuhara also enter the final eight.
The Denmark shuttler reduced the gap to 11-13 but Srikanth changed gears to produce another five-point burst to zoom ahead. The Indian eventually closed out the opening game without much ado.
Nothing much changed in the second game as Srikanth took a 11-3 lead but Anders came back strongly to reel off six points on the trot to reduce the margin to 9-11.
However, Srikanth continued to move ahead to open up a 20-15 lead. Antonsen saved three matches points before the Indian sealed the issue in his favour.
After the interval, Sindhu clawed back with two points but the duel between the two became more fierce as they moved neck and neck till 19-19 when the Hong Kong girl moved ahead to earn the bragging rights.
Jolted by the first game reversal, Sindhu opened up a 4-0 lead but Cheung drew parity at 9-9 before grabbing an 11-10 advantage at the interval. The Hong Kong girl then moved to a 16-13 lead.
In the decider, Sindhu moved to a 11-6 lead early on but Cheung once again caught up with the Indian at 12-12. Sindhu then distanced herself, reaching 15-12 before comfortably grabbing five match points at 20-15. Cheung saved two match points before the Indian shut the door on her rival.
Yesterday, Ajay Jayaram disposed off Netherland's Mark Caljouw in straight games to advance to the pre-quarterfinals but it was curtains for Sameer Verma and Rituparna Das at the World Championship.
National champion Rituparna too was hardly a match for local favourite Kirsty Gilmour, seeded 16th, as she went down 16-21 13-21 in a 42-minute clash.
Women's doubles pair of Sanjana Santosh and Arathi Sara Sunil also bowed out with a 14-21 15-21 loss to 14th seeded Chinese combination of Bao Yixin and Yu Xiaohan.