Dominic Thiem, who was the runner-up in the 2020 edition, will miss the Australian Open this year as he continues his recovery from a serious wrist injury.
The 28-year-old Austrian has not played since a second-round defeat in Mallorca in June, meaning he was unable to defend his US Open title in September.
“I will miss the Australian fans, but I will be back (there) in 2023,” he said on Twitter.
“We believe this is the right decision in order to have a good return to competition. For the moment I will remain in Austria for a few more days and then head to practice outdoors and get ready for my first event of the season,” he added.
There also remains significant doubt about World no.1 Novak Djokovic's participation as he remains tight-lipped about his Covid-19 vaccination status.
Rafael Nadal, Andrey Rublev and Denis Shapovalov are all recovering after testing positive for the virus in recent weeks.
Thiem, who has slipped to 15th in the rankings, reached the final at Melbourne Park last year before going on to win his maiden major title at Flushing Meadows.
