Novak Djokovic went through "rigorous" checks before being handed a medical exemption to compete at the Australian Open, tournament chiefs insisted.
A wave of criticism followed Djokovic's announcement that he was on his way to Melbourne for the season's first grand slam tournament.
The Serbian has not directly addressed whether he has been vaccinated against COVID-19, but players who compete at Melbourne Park either require proof they have been jabbed or an exemption.
He has spoken openly and critically about vaccine mandates, insisting there should be freedom of choice in all walks of life.
Many Australians on social media spoke out against the decision to welcome Djokovic into the country, predicting he could face a frosty reception while the country battles surging cases of the Omicron variant.
Djokovic will be bidding to win a 10th Australian Open title and a record 21st singles grand slam, more than any man in history.
The 34-year-old had his bags packed and was awaiting a flight at an airport when he broke the news of his trip to Australia on Tuesday.
Australian Open chiefs confirmed he had been granted permission to play, saying in a statement: "Novak Djokovic will compete at the Australian Open and is on his way to Australia.
"Djokovic applied for a medical exemption which was granted followting a rigorous review process involving two separate independent panels of medical experts. One of those was the independent medical exemption review panel appointed by the Victorian Department of Health."
Happy New Year! Wishing you all health, love & joy in every moment & may you feel love & respect towards all beings on this wonderful planet.— Novak Djokovic (@DjokerNole) January 4, 2022
I’ve spent fantastic quality time with loved ones over break & today I’m heading Down Under with an exemption permission. Let’s go 2022! pic.twitter.com/e688iSO2d4
There has been no detail given of why Djokovic qualified for an exemption, and unless he is willing to disclose personal medical information it is set to remain that way.
Australian Open tournament director Craig Tiley said it remained the case that all involved with the tournament, from fans through to players, must be fully vaccinated or have an exemption permission allowing them to attend.
Tiley said: "Fair and independent protocols were established for assessing medical exemption applications that will enable us to ensure Australian Open 2022 is safe and enjoyable for everyone.
"Central to this process was that the decisions were made by independent medical experts and that every applicant was given due consideration."
Explaining the process of securing exemptions, the Australian Open indicated in its statement that Djokovic would not have been treated as a special case.
It pointed out that a government-appointed panel assessed all cases that got past the first stage of checks, and that "the process included the redaction of personal information to ensure privacy for all applicants".
This should mean Djokovic was not identifiable to those making the crucial decisions about whether he should be allowed to take part.
"The multi-step independent review process was designed to ensure the safety of everyone at the Australian Open," the tournament statement added.