Former national champion Rituparna Das upset fifth seed Ksenia Polikarpova while Siril Verma eased through against Miha Ivanic to reach the women’s and men’s singles quarter-finals respectively at the Russian Open Super 100 badminton tournament in Vladivostok on Thursday.

Das, who has been struggling with injuries since the Premier Badminton League earlier this year, faced some challenge from Israel’s Polikarpova in the opening game but raced through the second with 11 consecutive points from 9-5 to win 21-18, 21-7 in just 29 minutes. She will now face top seed Kristy Gilmour of Scotland in the last eight round.

Later in the day, former junior world championship silver medallist Verma continued his good run in the competition as he hammered Ivanic 21-11, 21-7 in just 27 minutes. He has set up a quarter-final clash against fourth seed Ihsan Maulana Mustofa of Indonesia.

It was, however, not a good outing for SaarLorLux Open champion and top seed Subhankar Dey as he went down 21-18, 21-18 against Japan’s Kodai Naraoka in the men’s singles third round.

Also ending up on the losing side were C Rahul Yadav, who went down against sixth seed Pablo Abian 16-21, 21-12, 21-14 and G Vrushali, who lost to seventh seed Yu Po Pai of Chinese Taipei 19-21, 21-9, 21-12.

In the doubles events, women’s doubles top seed J Meghana and Poorvisha S Ram got the better of Anastasiia Kurdyukova and Anastassia Shapovalova 13-21, 21-12, 21-15. Meghana also advanced to the mixed doubles quarter-finals along with Dhruv Kapila as the Indian pair defeated Russian combination of Vladimir Nikulov and Anastasiia Semenova 13-21, 21-18, 22-20.