World number one Djokovic was paired with Miomir Kecmanovic in Thursday's draw for the opening round, but it remains uncertain whether he will even take part in the first grand slam of the year.

The Serbian was last week given a medical exemption to enter Australia, despite not being vaccinated, only for border officials to block it upon his arrival.

Djokovic was detained for four days while waiting to appeal the case on Monday, which went in his favour at Melbourne Circuit Court.

He has since started training ahead of the Australian Open, which begins next Monday, though immigration minister Alex Hawke may yet cancel his visa for a second time.

The 34-year-old is also being investigated for breaching isolation rules in December after testing positive for COVID-19.

And as a decision regarding whether he can stay in Australia and defend his title is dragged out, Tsitsipas has become the highest-profile tennis figure to criticise Djokovic for his conduct.

"He has been playing by his own rules," world number four Tsitsipas told Indian outlet WION.

"No one would have thought: 'I can come to Australia unvaccinated and not have to follow the protocols they gave me'.

"For Novak it worked another way. It takes a lot of daring to do. Putting a Grand Slam at risk – I don't think many players would do that."

Tsitsipas, who was defeated by Djokovic in last year's French Open final, added: "There are two ways to look at it.

"One way is that almost every single player has been vaccinated and did what they had to do in order to come and play in Australia.

"We have all followed the protocols to come and compete in Australia and been very disciplined in that.

"It seems like not everyone is playing by the rules of how Tennis Australia and some governments have been putting things.

"A very small minority chose to follow their own way. It makes the majority look like they are all fools."

Djokovic has spent the past four days training on court in preparation for the Australian Open, which he has won a record nine times, including in each of the last three years.

But weighing in on the debate on Thursday, Australian deputy prime minister Barnaby Joyce said the 20-time grand slam winner must "abide by the rules" if he is to remain in the country.

"You have to be frank – the vast majority of Australians said they didn't like the idea that another individual, whether they're a tennis player or the king of Spain or the queen of England, can come up here and have a different set of rules to what everybody else has to deal with," Joyce said.

"Let's see where it goes from here… I've made my views clear. I might not agree with the fact that I have to be tested to go from New South Wales into Queensland but I do [it’. Why? Because that is the law.

"He is no better. He is still a child of God like the rest of us, isn't he? So he has got to abide by the laws."