Tennis star Naomi Osaka made a heartwarming gesture after winning her opening match at the US Open.The Japanese player defeated Marie Bouzková of the Czech Republic 6-4, 6-1 at Flushing Meadows. Shortly after her victory, Osaka was seen running over to a little girl in the crowd and handing her a pin."I just heard her when I was playing my match and she was so cute," Osaka explained in her post-match interview. "So, thank you for cheering me on.""At the Olympics we got little pins that we were supposed to pass around to other players, trading pins, and I wasn't there for a long time so I have a couple in my bag leftover. But yeah, I thought it would be a nice little memory."

The heartwarming moment has now gone viral on social media after it was shared by ESPN, with fans describing the tennis player as a "class act".

Osaka was made to work in the first set of her match against Bouzková, but the 23-year-old eventually got a break at 5-4 up. She then ran away with it in the second set, allowing Bouzková to win only one game.

It was Osaka’s first victory in a Grand Slam since the French Open, which she withdrew from after declining to fulfil her media obligations. She revealed she had "suffered long bouts of depression" since winning the US Open in 2018 and claimed people often had "no regard for mental health" during press conferences.

Osaka remained away from the court for Wimbledon, but returned to competition for the Tokyo 2020 Olympics, losing in the third round. With the Games held behind closed doors, Osaka sounded happy to be playing in front of crowds again at Flushing Meadows.

Naomi Osaka revealed she enjoyed playing in front of a crowd at the US Open

"It feels kind of crazy to play in front of everyone again," she said. "Last year when we didn’t have a crowd it felt quite lonely for me. The energy here is unmatched.

"I'm just really glad to see little kids in the audience and of course grown-ups too. To be playing the first night match is something I've never done before so I'm just glad I won."

"I’ve played a lot of matches on this court, maybe the most in my career and I definitely feel comfortable here."

Osaka has won the US Open twice, earning her second title last year after her initial victory in 2018. She also was victorious at the Australian Open in 2019 and at the start of this year.