Melbourne: Two-time Australian Open champion Naomi Osaka on Sunday pulled out of the opening Grand Slam of the year just over a week before it starts, organisers said.
It was another big blow for the tournament after US Open champion and world number one Carlos Alcaraz also withdrew on Friday with a right leg problem.
"Naomi Osaka has withdrawn from the Australian Open. We will miss her at AO2023," the tournament said on Twitter. No reason for the Japanese star's withdrawal was given.
The champion in Melbourne in 2019 and 2021, Osaka has not played a competitive match since pulling out of a tournament in Tokyo in September with abdominal pain and has slumped to 42 in the world rankings.
Veteran American Venus Williams will also be a no-show after picking an injury at last week's Auckland Classic.
The four-time Grand Slam winner has previously talked about struggles with her mental health and spent all of 2022 outside the top 10, enduring first-round defeats at both the French and US Opens. She withdrew from Wimbledon with an Achilles' injury.
Speaking at the Pan Pacific Open in September, she admitted she had gone through "more down than up" in 2022.
"This year has been not the best year for me but I've learned a lot about myself," she said.
"Life is ups and downs, and this year was more down than up, but overall I'm pretty happy with where I am now."
Reports in Australia last week said Tennis Australia had been unable to verify Osaka's whereabouts.
Her social media accounts indicated that she had been travelling in Europe with her on-again off-again boyfriend rapper Cordae.