Reigning world champion PV Sindhu kept India's hopes of winning a first-ever Olympic gold in badminton alive as she reached the semifinals of women's singles with a fighting straight-game win over world no 5 Japanese Akane Yamaguchi.

The 26-year-old Indian, who won a silver in the 2016 Rio Olympics, defended brilliantly and rode on her attack to outclass the fourth-seeded Yamaguchi 21-13 22-20 in a 56-minute quarterfinal clash at the Musashino Forest Plaza. She will next face the winner of the other quarterfinal between Thailand's Ratchanok Inthanon and Chinese Taipei's Tai Tzu Ying.