'What a moment': Naomi Osaka's beautiful act for young US Open fan

Naomi Osaka provided the tennis world with another beautiful reminder about why she's such a fan favourite, with a lovely gesture for a young fan at the US Open.

The reigning champion cruised through to the second round of the year's final grand slam with a 6-4 6-1 victory over Czech Marie Bouzkova, that was temporary halted by a pesky moth that met an untimely end.

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The third seed allayed any fears about a lack of matches during what has been a turbulent year after her withdrawal from the French Open and decision to skip Wimbledon.

She was made to work hard for the opening set, saving three break points at 1-1 before eventually forcing the break to clinch it in game 10.

But Osaka, a two-time champion in New York, promptly raced away in the second set to register a solid victory to the delight of the big crowd inside Arthur Ashe Stadium.

"It feels kind of crazy to play in front of everyone again," she said in her on court interview.

"Last year when we didn't have a crowd it felt quite lonely for me. The energy here is unmatched.

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

“I’m glad to see little kids in the audience — and, of course, grown-ups, too.”

Osaka was then asked about a beautiful moment with one young fan after cameras capturing her walking over to present something to a small girl in the crowd.

"Actually I just heard her when I was playing my match and she was so cute so thank you for cheering me on, Osaka said as rapturous applause echoed around the stadium.

"In the Olympics we got little pins that we were supposed to pass around to other players, you know like trading pins," she added.

"And I wasn't there for a long time so I have a couple in my bag that are left over so I thought it would be a nice little memory (for her)."

Osaka has been in a charitable mood during her time in New York, with the four-time major winner paying to have courts in her old neighbourhood refurbished.

The 23-year-old last week went back to the courts in Queens where she grew up playing tennis from age three until she was eight, when her family subsequently moved to Florida.

“It definitely meant a lot to me … just to revisit my old courts and see familiar faces,” Osaka said about the visit.

Osaka is joined in the second round at Flushing meadows by fellow big guns such as Aryna Sabalenka, Simona Halep and Garbine Muguruza.

Naomi Osaka joined in next round by big guns

Sabalenka, the second seed from Belarus, needed three sets to get past Nina Stojanovic of Serbia.

The Belarusian, who recently overtook Osaka in the rankings, dropped the second set in a tiebreaker but powered home to win 6-4 6-7 (4-7) 6-0.

Halep and Muguruza, a pair of two-time grand slam champions, came through tough draws with battling two-set victories.

Halep held off Montreal champion Camila Giorgi 6-4 7-6 (7-3).

The Romanian, who did not play in last year's behind-closed-doors event, missed the French Open, Wimbledon and the Olympics with a calf injury.

"For me it was normal to have the people in the stands and the noise that is always in the US Open," Halep said.

"I started to like it. I start to embrace these things. I had fun on court, and I liked some people that were screaming in Romanian also and in English."

Muguruza, the ninth seed, also came through a tricky opening-round, advancing with a 7-6 (7-4) 7-6 (7-5) victory over Donna Vekic.

Former champion Angelique Kerber bounced back from the brink of defeat to beat Dayana Yastremska 3-6 6-4 7-6 (7-3) while fifth seed Elina Svitolina sank Rebecca Marino 6-2 6-3.

Teenager Coco Gauff came from a set down to beat Poland's Magda Linette 5-7 6-3 6-4.

The 17-year-old 21st seed will meet fellow American Sloane Stephens in the second round after she accounted for countrywoman Madison Keys 6-3 1-6 7-6 (9-7) in a rematch of their 2017 final.

Aussie World No.1 Ash Barty gets her campaign underway on Wednesday morning (AEST) against 2010 finalist Vera Vera Zvonareva.

with AAP

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