Saina, who was the top seed in the tournament, lost 21-13, 12-21, 18-21 in 53 minutes.

The Hyderabadi shuttler started the match on the front foot, never giving her opponent even a sniff of a chance in the opening game. However, her fortunes changed dramatically in the next game in which she won just two consecutive points.

Saina Nehwal
Saina Nehwal. Pic/ AFP

It was neck and neck in the early part of the second game but after the score reached 6-6, Gu seemed to up the ante and never relinquished the lead thereafter.

The third game was an up and down battle with both players trading the lead. Gu, though, trailing 13-15 took the initiative winning six points in a row to take the score to 19-15 in her favour.

Saina made a comeback of her own reducing the deficit to just one (18-19) but the Singaporean held her nerve to win her final two points and book a place in the semis where she will face seventh seeded Thai Busanan Ongbumrungpan.