Emma Raducanu has pulled out of her first event of the season at the ASB Classic in Auckland after suffering a back problem.

And the British No.2 now plans to fly to Melbourne and prepare for the Australian Open without a competitive warm-up match.

The former US Open winner added Maria Sharapova’s former fitness trainer Yutaka Nakamura to her team last month in a bid to end her long list of injury problems.

But Raducanu, 22, had her preparations disrupted by a “back niggle” before Christmas and she has failed to regain full fitness.

She said. “I tried my best to be ready. I love Auckland and the fans here but unfortunately picked up a back niggle and won’t be ready in time.”

And her condition has not improved enough for her to play her opening match against American Robin Montgomery in New Zealand.

World No.56 Raducanu twisted her left ankle playing on the indoor courts in Auckland in the second round in January 2023 and then lost in the second round in Melbourne.

The Bromley-based star also suffered a foot ligament injury in the quarter-finals of the Korea Open in September - her last appearance on the WTA Tour. She won all three matches at the Billie Jean King Cup finals in Malaga last month.

After missing most of 2023 after wrist and ankle surgeries, this summer Raducanu had made the semi-finals in Nottingham, beat Jessica Pegula at Eastbourne and reached the Wimbledon fourth round - her best Grand Slam performance since her New York triumph.

She had been No.6 seed in Auckland - the first time she had been seeded at a WTA event since the 2022 Korea Open - but has again been let down by her body.

Raducanu had stated her aim was to play more events in 2025 with the help of regular training sessions on the road with Japanese trainer Nakamura.

Speaking earlier this month, she said: “I think he is going to help me just really explore how far I can go, like athletically. I think it’s a big strength of mine that I have nowhere near fulfilled.

“I think I can become one of the best athletes out there in tennis and I’m just looking forward to seeing how much I can do.”

British No. 1 Jack Draper pulled out of the United Cup this week to protect a hip injury. The Australian Open starts in Melbourne on Sunday January 12.