"I'm happy about what I did here. I love the people here, the crowd," Wu said. "Many Chinese people came to support, I love it."

Wu had played his way into the field through the qualifying tournament, joining countryman and fellow qualifier Zhang Zhizhen as the first Chinese men in the US Open main draw since the open era began in 1968.

Wu was almost joined in the second round by Zhang, China's top-ranked player, but the 25-year-old was beaten by Tim van Rijthoven of the Netherlands, who saved seven match points in the third set to seal a 3-6 6-7, 7-6, 6-1, 6-4 victory.

"We are both pushing Chinese men's tennis levels, and we're still young. ... I think we're going to get to the Top 100," Wu added.

Wu, who made it through three qualifying matches, now can walk in the footsteps of China's Fu Chi Mei, who beat Ron Barnes in the first round of the 1959 Wimbledon Championships in England.

Wu is also the first Chinese man to win a US Open singles match since Cheng Guy did it in 1935.

Wu entered the US Open in good form, having won two ATP Challenger titles back to back. He also has soared in the rankings, moving from 1,869 in March to a career-high 174 now.

He was the world's No 1 junior and clinched the boys' singles and doubles titles at Flushing Meadows in 2017 to become the first Chinese male to win a Grand Slam title of any kind.

But it has not been an easy path for the prodigy, as he did not play from March 2019 to January 2022 due to injuries to his elbow, which required back, shoulder and wrist surgeries.

"I don't really like to talk about those injuries in too (much) detail because every player has injuries," Wu had told the ATP website. "The mental strength that you have to go through the pain is part of the game."

Wu next faces Portuguese qualifier Nuno Borges, who defeated American wildcard Ben Shelton, on Wednesday.

Agencies contributed to this story.