Saina, seeded third in the event, beat 15th seed Buranaprasertsuk 18-21 21-16 21-14 in a clash which lasted 52 minutes. With this win, Saina also kept her all-win record against Buranaprasertsuk intact, having beaten her in their five previous encounters before today.
Saina's most recent win against Buranaprasertsuk came last year during the Thailand Open. Saina will next take on the winner of other prequarterfinal match between Sayaka Takahashi of Japan and Korea's Yeon Ju Bae, who has been seeded 13th in the event.
Buranaprasertsuk started off strongly today and surprised the Indian with better command over smash winners, sending down 11 of them in the first game. But Saina regained her composure pretty quickly and roared back in the second game with nine of her trademark smash winners.
She kept up the pressure in the deciding game as well to emerge triumphant after the initial scare.