Coco Gauff joined a sparkling Naomi Osaka, rampant Iga Swiatek and defending champion Jannik Sinner in next round of the US Open on Tuesday.

Gauff, who was playing her first match since adding biomechanics expert Gavin MacMillan to her coaching team in order to help with her shaky serving, navigated a big test against unseeded Ajla Tomljanovic 6-4 6-7 (2-7) 7-5.

“It wasn’t the best,” Gauff said, “but I’m happy to get through.”

The 2023 champion dropped the opening game and produced a flurry of errors but soon shook off the cobwebs and grabbed a 5-4 lead with an ace out wide, eventually taking the first set with a decisive break.

Tomljanovic, who famously battled past Serena Williams in three sets at Flushing Meadows in 2022, was in need of a similar fightback when Gauff built up a 4-2 lead in the second set.

The Australian rallied bravely from there to move ahead 5-4 before squandering two set points, but composed herself quickly and forced a tie-break, where she raised her game again to make it one set apiece.

A nervous Gauff made consecutive double faults when serving at 5-4 in the decider before regaining composure to wrap up the victory and book a second-round encounter with Paris Olympics silver medallist Donna Vekic.

Naomi Osaka turned heads with a sparkling display against Belgium’s Greet Minnen 6-3 6-4 to storm into the second round at Flushing Meadows.

The two-time champion entered the court with sparkly red roses in her ponytail above her red outfit and even a matching Labubu that she named ‘Billie Jean Bling’.

Minnen, ranked 106th, had her moments of defiance, briefly leading 4-3 in the second set before reality came crashing down.

Her 30 unforced errors and a 49 per cent first-serve percentage told the story of a player overwhelmed by Osaka’s baseline barrage.

Osaka said the work on her crystalised Nike outfit started long ago and the plan for the hair accessory – which she removed before the match – came together more recently.

“It was really elaborate, because the crystals are really hard to do on a performance outfit,” Osaka said.

“I just thought it would be really fun to do a New York under the lights. I’m glad that my first match was a night match, because this outfit was really fun to play. This is my night outfit, so hopefully I’ll wear my day outfit next time.”

Next up is American Hailey Baptiste, whom Osaka described as a player who “is able to do basically anything.”

The two-time US Open champion is aiming to become the first mother to capture a Grand Slam singles title since Kim Clijsters conquered the Australian Open in 2011.

Swiatek breaks Monica Seles’ record

Iga Swiatek set a new record with a dominant first-round victory over Emiliana Arango at the US Open.

The Wimbledon champion continued her impressive summer form with a 6-1 6-2 stroll against Colombian Arango on Arthur Ashe Stadium to cruise into round two.

Swiatek has now won her opening match at 65 consecutive tournaments, breaking the previous open era record set by Monica Seles.

While the Pole is seeded second behind Aryna Sabalenka, she appears to be the player to beat at Flushing Meadows having followed up her Wimbledon triumph by winning the big WTA event in Cincinnati last week.

Swiatek seemed more excited about news of Taylor Swift’s engagement than her own victory, but she was happy to have made a confident start.

“First matches are always a bit different, so I’m happy that I had some time to just get used to the conditions and the surface, because for sure it’s different than the practice courts,” said the Pole, who won her only title here in 2022 and next faces Dutchwoman Suzan Lamens.

“I think it was just a solid match, and so I’m happy that I can play another round here.”

Sinner back to full health in classy opening win

Defending champion Jannik Sinner was in tears after retiring in the final of the Masters 1000 event in Cincinnati against Carlos Alcaraz last week because of illness but looked back to full health as he sprinted to a 6-1 6-1 6-2 victory against Czech Vit Kopriva.

Sinner needed only an hour and 38 minutes to wrap up victory on Arthur Ashe Stadium, and he said: “I feel in a good shape physically.

“Has been some good practice days, especially the last couple. I feel physically in a good spot. Also good first-round match, so I’m very happy.”

Sinner could face a stiffer test next against big-hitting Australian Alexei Popyrin, who defeated Novak Djokovic here last year.

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