Alex de Minaur is confident his injury woes are behind him, feeling he is in the best shape he has ever been ahead of the Australian Open.

The world No.9 recaptured his fluid best at the first United Cup round in Sydney, putting on a commanding performance to beat Argentina’s Tomas Etcheverry 6-1 6-4 at Ken Rosewall Arena.

De Minaur had been plagued by a hip injury in his breakout 2024 season suffered during his Wimbledon run in July.

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The 25-year-old had risen as high as world No.6 after reaching the second week of every slam, including quarter-finals of the French Open, Wimbledon and US Open.

Australia’s No.1 remained hindered by the troublesome hip while playing in the Davis Cup in November, but he now feels the worst is over having returned to Australia.

“It’s definitely the best I felt since Wimbledon,” de Minaur said on Saturday.

“Very happy with how the body’s moving, how it’s feeling.

“It’s been a long time coming but it’s feeling the best shape it has been in a very, very long time.”

De Minaur is primed to enjoy a rich vein of form heading into next month’s AO, having been the only Australian to claim a victory against Argentina in their first United Cup match.

He put on a clinical performance against Etcheverry, claiming the first set within 28 minutes on his way to levelling the tie after teammate Olivia Gadecki lost 6-2 6-4 to Nadia Podoroska in the women’s single.

“I was extremely pleased with my level (of performance). Being the first match of the new season, you never know what to expect,” de Minaur said.

“Tommy, he’s a quality opponent, a very tough opponent, so I was happy in the way I executed today from the very start until the end.

“It’s a very special court and a court that I love playing on, so I was very happy to be able to play the match today.”

Australian captain Lleyton Hewitt said de Minaur “played fantastic tennis”.

“He was very confident out there, right from the word go, played his Plan A out there, and executed incredibly well,” he said.

“He played a faultless match, really.”

In the women’s singles, emerging star Olivia Gadecki battled nerves and was broken in her opening game, before losing the first set.

Cheered on by a boisterous home crowd in the second, the 22-year-old looked ready to mount a comeback after launching ahead 4-3 but was ultimately undone by her errors in the 88-minute contest.

“I thought Olivia got better as the match went on,” Hewitt said.

“If we could have snuck out the second set and taken it to a deciding, I think she would have got better throughout the third set.”

Argentina secured the 2-1 win thanks to a strong performance from Etcheverry and Maria Carle against Matt Ebden and Ellen Perez, the South American pair claiming a 6-2 6-4 result.

Australia return to the court on New Year’s Day when they face a Great Britain outfit including Billy Harris and de Minaur’s fiancee Katie Boulter.