The 34-year-old's quest for a 10th title at Melbourne Park goes on the line when his legal team attempt to overturn his visa cancellation and deportation orders from the Immigration Minister Alex Hawke

The top seed needs to be on the tennis court on Monday for an opening-round clash with Serbian compatriot Miomir Kecmanovic, while Open organisers are poised to maker draw changes should Djokovic's last-ditch legal bid fail.

The Serbian superstar was on Saturday afternoon returned to the Melbourne immigration detention hotel where he'd already spent four nights.

Wearing a green tracksuit and a white face mask, he appeared composed in the back of a vehicle.

Earlier in the day his lawyers fronted a brief procedural hearing before Justice David O'Callaghan in the Federal Court, after the case was transferred from the Federal Circuit Court following a late-night hearing on Friday.

The question of whether Sunday's hearing will be held before a single judge or a full court is still to be determined.

In an 268-page affidavit released on Saturday by the Federal Court, Hawke's detailed reasons for using his discretionary power to cancel Djokovic's visa a second time were outlined.

In it, Hawke suggested the unvaccinated world No.1's presence during the tournament could encourage residents to shirk COVID-19 isolation rules, given he's acknowleged doing so last month, and foster "anti-vaccination sentiment".

Djokovic's lawyers flatly rejected the claim in their grounds for appealing the visa cancellation, saying the minister had not cited any evidence to back it up.

They argued that booting Djokovic out of the country could excite similar anti-vaccination sentiments.

Djokovic came under added scrutiny this week when he admitted in a statement he had provided false information on his travel declaration, blaming his agent for the error.

He also admitted attending a media interview in Serbia while knowingly COVID-19 positive and meant be self-isolating, calling it an "error of judgement".

Serbian President Aleksandar Vucic has accused the Australian government of "harassing" and "maltreating" Djokovic, suggesting it was indulging in political point-scoring ahead of the election.

But Prime Minister Scott Morrison insists Djokovic's visa cancellation was done in the public interest.

World No.2 Daniil Medvedev will take over as top seed should Djokovic's be ruled out. The Russian lost the Australian Open final to Djokovic last year then beat him in the US Open final.

While his chances of a second grand slam title would increase in the Serb's absence, Medvedev wanted to know more about the procedure and reasons behind his rival's expulsion.

"I want to say about Novak's situation that we're in Australia, it's their rules," Medvedev said on Saturday.

"If he has a valid exemption to be in this country and to do what he wants, then he should play and if the exemption is not valid or something else is not valid, well, any country can deny your entry

"I know yesterday the Prime Minister ... said no and I didn't really read anywhere why - that's what interests me to know, the reason.

"Is it just he said, I don't want? Is there a real legal reason behind this? I guess we're going to know a little bit more tomorrow at the appeal."

Spanish great Rafael Nadal also stands to benefit, as an Australian Open crown would move him clear of his long-time rivals Djokovic and the absent Roger Federer with 21 grand slam titles.

"Australian Open is much more important than any player," Nadal said. "If he's playing finally, OK. If he's not playing, Australian Open will be great Australian Open with or without him."

Australian Associated Press