Twice bronze medallist at the World Championships, Sindhu scored a hard-fought 21-13, 13-21, 21-14 victory over Kaori Imabeppu and extended her overall record against the Japanese to 3-0, having beaten her in the World Championships and Japan Open in 2012 and 2013 respectively.
The third seeded Indian will meet Indonesia's Lindaweni Fanetri next.
Second seed Srikanth, who won the India Super Series and Swiss Open last year, thrashed 16th seed Boonsak Ponsana of Thailand 21-17, 21-10 in a men's singles match.
It was the world No 9’s second victory in three meetings against the Thai. He will meet China's Huang Yuxiang next.
Ajay Jayaram, seeded 10th, also progressed to the last eight stage, winning 11-21, 21-8, 22-20 against Malaysia's Zulfadli Zulkiffli.
He will meet the winner of the match between top seed Lee Chong Wei of Malaysia and Singapore's Zi Liang Derek Wong.
However, it was curtains for the Indian women's doubles pair of Jwala Gutta and Ashwini Ponappa. They lost their second round match 14-21, 17-21 to the Japanese duo of Shizuka Matsuo and Mami Naito in just 37 minutes.
Late on Wednesday, Sindhu and Srikanth stormed into the pre-quarter-finals.
Sindhu, seeded third, thrashed Switzerland's Sabrina Jaquet 21-17, 21-16 in a women's singles first round contest that lasted 33 minutes, while Srikanth first brushed aside Malaysia's Wei Feng Chong 21-17, 21-11 in his opening men's singles match before notching up another comfortable 21-16, 21-15 win over Christie Jonatan of Indonesia.
Jayaram first beat Japan's Takuma Ueda 21-19, 21-11 in his opening round before disposing off Petr Koukal of the Czech Republic 21-17, 21-17 in his second match of the day.
B Sai Praneeth, however, failed to get past the second round as he lost to third seed Tommy Sugiarto of Indonesia 14-21, 21-10, 18-21. He had beaten Malaysia's Shahzan Shah Misfahul 21-13, 21-15 in his opening round match.
Sameer Verma, another Indian, also started with a win, shocking Japan's Sho Sasaki, seeded 12th, 21-18 21-18 but made an exit after losing to Huat Soon Goh of Malaysia 21-7, 13-21, 16-21 in the second round.
Subhankar Dey notched a 21-19, 21-16 victory over Thailand's Kantaphon Wangcharoen in a men's singles first round match.
Image: Kidambi Srikanth
Photograph: Warren Little/Getty Images for Falcon
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