Unvaccinated tennis star Novak Djokovic has won the right to take his fight against deportation from Australia to a Federal Court, after the Government cancelled his visa for the second time over COVID-19 entry regulations.
The Government undertook not to deport him until the case was over, although the world's No.1 player was nevertheless ordered to return to pre-deportation detention.
His legal team submitted their appeal late at night - less than three hours after Immigration Minister Alex Hawke used discretionary powers to revoke the visa - in the hope that he could still begin the defence of his Australian Open title on Monday.
They will argue that Djokovic's deportation could be just as much of a threat to public health, by fanning anti-vaccine sentiment, as letting him stay and exempting him from Australia's requirement that all visitors must be vaccinated.
While Prime Minister Scott Morrison's Government has won support at home for its tough stance on border security during the pandemic, it has not escaped criticism for the seemingly inconsistent handling of Djokovic's visa application.
The 34-year-old Serbian, bidding for a record 21st Grand Slam title, was told on arrival on January 5 that the medical exemption that enabled him to travel was invalid.
He spent several days in immigration detention in a hotel also used for asylum-seekers, before that decision was revoked on procedural grounds.
Hawke says he exercised his prerogative to cancel the visa "on health and good order grounds, on the basis that it was in the public interest to do so".
He says he considered information from Djokovic and the authorities, and that the Government was "firmly committed to protecting Australia's borders, particularly in relation to the COVID-19 pandemic".
Judge Anthony Kelly, who revoked the first cancellation, says the Government has agreed not to deport Djokovic before the case concluded, and the player could leave detention to meet his lawyers and attend hearings.
Although Djokovic has publicly opposed compulsory vaccination, he has not campaigned against vaccination in general.
The controversy has intensified a global debate over the rights of the unvaccinated and become a tricky political issue for Morrison, as he prepares for an election due by May.
"Australians have made many sacrifices during this pandemic and they rightly expect the result of those sacrifices to be protected," Morrison says. "This is what the Minister is doing in taking this action today.
"Our strong border protection policies have kept Australians safe."
Australia has endured some of the world's longest lockdowns and has seen a runaway Omicron outbreak bring nearly a million cases in the last two weeks.
More than 90 percent of Australian adults are vaccinated and an online poll by the News Corp media group found that 83 percent favoured deportation for Djokovic.
His cause was not helped by an incorrect entry declaration, where a box was ticked stating he had not travelled abroad in the two weeks before leaving for Australia. In fact, he had travelled between Spain and Serbia.
Djokovic blamed the error on his agent, and acknowledged he also should not have done an interview and photoshoot for a French newspaper on December 18, while infected with COVID-19.