Shang will next challenge Nuno Borges, Portugal's world No 51, on Monday in the round of 32.

"It's an unbelievable match against Karen today. He's a very solid top-10 player. Coming into the match I didn't think too much, I just wanted to put on a show for the people," Shang said during his on-court interview after the win.

"I didn't start perfectly in the match, but I kept fighting, kept focusing, no matter winning or losing. Glad that I got the win. Overall, I am happy with my performance, even if I had gone down with a loss."

Apart from his composure and precision, Shang attributed his scintillating form to the energy from his cheering family in the stands, including vocal support from his grandmother.

"I am super happy to have family here," Shang said. "Winning here at such a big stage means a lot, especially at home, and having them watch me is incredible."

Shang's third-round appearance in Shanghai, where he was eliminated by world No 1 Carlos Alcaraz in the second round last year, has given him a much needed confidence boost amid a tough season that saw him sidelined with a foot injury for half a year, ever since the Australian Open.