The all-Indian quarterfinal clash started with a fiercely contested first game, where Hooda held her nerve to win it 23-21.
Hooda was off to a great start, racing to an 11-3 lead before Sihag staged a spirited comeback to level the scores at 21-21.
The 18-year-old Hooda will next face the winner of the quarterfinal between Chinese Taipei's Chiu Pin-chian and Vietnam's Nguyen Thuy Linh.
India's Unnati Hooda clinched a straight-game 23-21, 21-16 victory over Devika Sihag to reach the Taipei Open semifinals on Friday.
The all-Indian quarterfinal clash started with a fiercely contested first game, where Hooda held her nerve to win it 23-21.
Hooda was off to a great start, racing to an 11-3 lead before Sihag staged a spirited comeback to level the scores at 21-21.
However, Hooda held her composure in the closing stages, winning the next two points to clinch the opening game.
In the second game, the third seeded Hooda maintained her momentum and capitalised on her leads to wrap up the match 21-16 against eighth seed Sihag in 42 minutes.
The 18-year-old Hooda will next face the winner of the quarterfinal between Chinese Taipei's Chiu Pin-chian and Vietnam's Nguyen Thuy Linh.
Later in the day, Tanvi Sharma and Kiran George will play their respective singles quarterfinals against Thailand's Supanida Katethong and Japan's Yudai Okimoto.
