Giang was the sole Vietnamese player in the singles event after all others, including top seed Ly Hoang Nam, were eliminated.
The Hanoian player’s quick loss of 6-0 in the first set made people assume that further rounds would not have any athlete representing the hosts.
However, after a short break, Giang put up a miracle performance to level the score at 6-3 in the second set.
The third set saw an equal game between Giang, a wild-card holder, and No. 2 seed Singh as they forced the set to be tied. Giang, with the support of the home crowd, won 8-6 in the tie-breaker and advanced to the quarter-final.
His next rival is Pruchya Isaro of Thailand. The No. 7 seed booked his berth here after beating Niki KaliyandaPoonacha of India 7-6 (3), 6-4.
In another quarter final, No. 4 seed Alexios Halebian of Australia will play No. 5 Yu Cheng-Yu of Chinese Taipei; South Korean Son Ji-hoon, who beat Nam in the first round, will face Japanese Takashi Saito; and Nam Ji-sung, another South Korean, will be up against Abhinav Shanmugan of India who beat No 6 seed Ryota Tanuma from Japan 6-4, 6-4.
In the doubles event, Vietnamese Nguyen Bui Tri and his Australian partner Jayden Court were defeated 4-6, 3-6 by Kittirat Kerdlaphee and Palaphoom Kovapitukted of Thailand in the second round.