Nick Kyrgios withdrew from the Australian Open on Saturday as he continues to struggle for fitness after a long injury absence, calling the decision "heartbreaking".

The Australian showstopper had knee surgery in January and then aborted plans to return at Wimbledon after tearing a ligament in his wrist.

He said last month "the stars would need to align" for him to be ready for his home Grand Slam in January, and the one-time world number 13 confirmed on Saturday time had run out.

"So, this is a very disappointing time for me, but I won't be able to compete at the 2024 Australian Open," Kyrgios said on the subscription website OnlyFans, which he joined as a content creator last week.

"Obviously, heartbreaking. I've had so many amazing memories there, and I just want to really get back to playing at the top of my game and doing it right, and I need a little more time.

"Even though I won't be there competing this year at the AO, I still will be around, commentating matches, being around," he added.

Last month, Kyrgios said that winning a Grand Slam remained his driving force, having come closest at Wimbledon in 2022 when he lost to Novak Djokovic in the final.

The Australian Open runs from January 14-28 at Melbourne Park, with Aryna Sabalenka defending the women's title and Djokovic, the men's.

While Kyrgios will be missing, 22-time Grand Slam winner Rafael Nadal -- who has not played since this year's Australian Open due to injury -- is on the entry list.

So too is four-time Grand Slam champion Naomi Osaka, who gave birth to daughter Shai in July. She has not played since September 2022, having also struggled with her mental health.