Demirbag, who had upset Kirsty Gilmour in her opening round, continued to impress by beating Ukraine’s Maria Ulitina 21-13 21-17 on Thursday, and will next take on third seed Michelle Li.
In the lower half of the draw, Neslihan Yigit was pushed to three games by Estonia’s Kristin Kuuba, getting through 21-12 19-21 21-13 and advancing to a quarterfinal showdown with Busanan Ongbamrungphan.
Meanwhile, second seed Pornpawee Chochuwong was beaten by younger Thai compatriot Phittayaporn Chaiwan 21-12 21-16.
In men’s singles, India’s Lakshya Sen and Kidambi Srikanth progressed to the quarterfinals. While Sen got the better of fourth seed Wang Tzu Wei in straight games, Kidambi needed three games to outplay Lee Dong Keun.
Indonesia dominated men’s doubles, ensuring all four quarterfinals places in the lower half of the draw. Pramudya Kusumawardana/Yeremia Erich Yoche Yacob Rambitan edged eighth seeds Lu Ching Yao/Yang Po Han in a long match, 25-23 14-21 21-19, and will face third seeds Fajar Alfian/Muhammad Rian Ardianto.
World junior champions Leo Rolly Carnando/Daniel Marthin breezed past Scottish pair Alexander Dunn/Adam Hall 21-16 21-11 and face senior compatriots Mohammad Ahsan/Hendra Setiawan.
At the top of the draw, Marcus Fernaldi Gideon/Kevin Sanjaya Sukamuljo shook off te combative Ruben Jille/Ties Van Der Lecq of Netherlands, 23-21 21-18.
Indonesia had further cause for cheer in women’s doubles, with two pairs – Nita Violina Marwah/Putri Syaikah and Siti Fadia Silva Ramadhanti/Ribka Sugiarto – making the quarterfinals.
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