The Morrison government is now investigating the possible inaccuracy of Novak Djokovic's travel declaration, as Serbia continues its pressure on Australia over the treatment of the tennis star.
Serbian Prime Minister Ana Brnabić told Scott Morrison in a call on Tuesday morning Australian time that Djokovic's rights should be respected.
Brnabić, who sought the call, asked Morrison to do all in his power to ensure Djokovic would have humane and dignified treatment in Australia, according to a report from a Serbian news agency.
A readout from Morrison's office described the call as "constructive".
"The PM explained our non-discriminatory border policy and its role in protecting Australia during the COVID-19 pandemic," the readout said.
"They both agreed to stay in contact on the issue, and to further strengthening the bilateral relationship."
Djokovic's visa was restored in a federal circuit court win on Monday, when the Commonwealth admitted Border Force had not afforded him procedural fairness last week when his visa was cancelled.
The cancellation was on the grounds he had not met the criteria for a medical exemption from vaccination.
Attention turns to the word 'no'
But now official attention has also turned to his travel declaration. The declaration asks arrivals, "Have you travelled, or will you travel, in the 14 days prior to your flight to Australia?" His form said no.
Djokovic, who lives in Spain, left from there for Australia on January 4, transiting through Dubai. Social media had him in Belgrade on December 25. Border Force is looking into whether the information in the declaration was inaccurate.
Immigration Minister Alex Hawke is currently considering whether to use his discretion to cancel Djokovic's visa again.
The government concedes Border Force blundered on procedural fairness but it still contends Djokovic has not met the vaccination exemption criteria.
Hawke's spokesman on Tuesday said the visa issue was "ongoing".
The minister is considering a brief that contains material from both the Home Affairs department, and Djokovic.
Meanwhile, despite the uncertainty about his prospects of playing in it, after his days of enforced confinement Djokovic is now back on court preparing for the Australian Open.
After Monday's result, he posted on social media that "despite all that has happened, I want to stay and try to compete" at the Australian Open.
"I remain focused on that. I flew here to play at one of the most important events we have in front of the amazing fans," he said.
There are mixed views in the government on whether it should cancel Djokovic's visa again.
Liberal backbencher and former professional tennis player John Alexander said that after the court outcome it would be a mistake for Hawke to use his ministerial power to deport Djokovic.
Alexander pointed the finger at Border Force, telling the ABC that "the person who processed Novak possibly made an error, late at night".
Author: Michelle Grattan - Professorial Fellow, University of Canberra