The father of Hong Kong, China tennis star, Coleman Wong, said his son's historic journey at the US Open felt very much like a dream despite his defeat in the third round.

Wong, ranked 173th in the world, fought for all five sets and bowed out 2-3 to Russian Andrey Rublev, who's 15th in the world rankings.

Coleman Wong's father, Bruce, who flew with his wife at short notice to attend the game in New York, said he was pleased and happy with his son's effort.

Speaking with RTHK, he noted that the players Coleman defeated in the earlier rounds were ranked above him as he became the first player from Hong Kong, China to ever win a Grand Slam singles match in the Open era.

The father said while his son, 21, was a bit disappointed with the loss, he believed Coleman punched above his weight against Rublev.

"The performance, I think anyone who watched the game will say that Coleman has already performed very well," Bruce Wong said.

"I think after this match, the world will know there is a player coming from Hong Kong. His name is Coleman Wong."

The father noted that at first, the stands at Flushing Meadows were about half full, but as the game went on and things got more intense, a capacity crowd of more than 8,000 was on hand.

He said there were touching moments when most of them cheered Coleman on, with him being the underdog.

Bruce said Coleman plans to compete in the Davis Cup in Hong Kong in mid-September, before heading to Chengdu, Beijing and Shanghai for tournaments there.

The father, who's also a primary school principal, said the key to being a good parent is to listen to your children, while finding ways to handle pressure together.

He noted that Coleman started learning tennis at five and played competitively since he was eight, and so as parents, they had tried different ways to help him cope with his pressures.

"After every win or every loss, they have different feelings, I think just let them speak out, talk about things that they want to improve, that's the first thing," Bruce said.

"When everything calms down, we will just take a seat and then discuss what we need to do in the future and set another goal."

For her part, sports minister Rosanna Law took to social media to congratulate Coleman Wong for his "amazing journey".

"The end of the current [journey] is the beginning of the next one. We are proud of you, Coleman!!!" she wrote shortly after the match.