The Australian government says Novak Djokovic's mere presence during the Australian Open could stoke "anti-vaccination sentiment" and encourage others to disregard isolation rules.
In an email outlining his detailed reasons for cancelling Djokovic's visa for a second time, Immigration Minister Alex Hawke conceded the unvaccinated tennis star poses a "negligible" risk of spreading Covid-19 to others.
However, he argues allowing the 20-time grand slam winner to remain Down Under may be a risk "to the health of the Australian community".
"I have given consideration to the fact that Mr Djokovic is a high profile unvaccinated individual who has indicated publicly that he is opposed to becoming vaccinated against Covid-19," Hawke wrote.
"In addition, I consider that Mr Djokovic's ongoing presence in Australia may lead to an increase in anti-vaccination sentiment generated in the Australian community, potentially leading to an increase in civil unrest of the kind previously experienced in Australia with rallies and protests which may themselves be a source of community transmission."
The minister says it could also lead to other unvaccinated Australians refusing to get the jab, anti-vaxxers having their views reinforced and a reduction in the uptake of booster doses.
Referencing Djokovic's self-described "error in judgement" to proceed with an interview with a French magazine journalist last month after being informed of his positive Covid-19 result, Hawke said that may "foster similar disregard for the precautionary requirements following receipt of a positive Covid-19 test in Australia".
"His behaviour may encourage or influence others to emulate his prior conduct and fail to comply with appropriate health measures following a positive Covid-19 test, which itself could lead to the transmission of the disease and serious risk to their health and others," he wrote.
The world No.1's false Australian travel declaration, which suggested he had not travelled in the past 14 days before arriving in Melbourne, was not a factor in the decision after the player's agent provided a statutory declaration accepting responsibility.
The minister said he considered the likely "significant" inconvenience, emotional hardship and distress of cancelling Djokovic's visa, on top of possible reputational damage and professional implications including his inability to compete in the Australian Open.
But ultimately Hawke decided the long list of health, good order and public interest ramifications outweighed the personal damage it could potentially cause the tennis star.
"These matters go to the very preservation of life and health of many members of the general community and further are crucial to maintaining the health system in Australia, which is facing increasing strain in the current circumstances of the pandemic," he said.
Earlier, there was no sign of Djokovic during Saturday's procedural hearing of the Federal Court of Australia.
The 34-year-old had been due to meet with immigration officials at an undisclosed location in Melbourne at 8am (local time) on Saturday before being detained.
Justice O'Callaghan raised the possibility of convening a full court of three judges for Sunday's hearing, scheduled for 9.30am (local time), instead of a single judge.
It was supported was Djokovic's representative Paul Holdenson QC, but opposed by the government on appeal grounds.
"Having the matter referred to the full court would remove any party's right to appeal," said Stephen Lloyd SC, representing Hawke.
A decision on whether a full court will sit is expected later in the day.