P V Sindhu and H S Prannoy today stormed into the semi-finals of the Macau Open Grand Prix Gold Badminton Tournament. Prannoy, seeded third, defeated Sony Dwi Kuncoro of Indonesia 21-19 21-17. World No. 11 Sindhu prevailed over the fifth seeded China's Han Li 21-17, 19-21, 21-16. She will next take on Busanan Ongbumrungpan of Thailand in the semis.