Andy Murray refused to add to Novak Djokovic's troubles after the Serbian star's visa saga reared up again, insisting he would not "start kicking Novak while he's down".

Some players have been critical of Djokovic, while world number four Stefanos Tsitsipas said the Serbian has been "playing by his own rules" after refusing to be vaccinated against the COVID-19 virus.

Djokovic faces a critical Federal Court hearing on Sunday that looks set to determine whether he can play at the Australian Open, which starts the following day.

Although the Serbian arrived in Australia with a medical exemption for the grand slam tournament, which he has won on a record nine occasions, that did not satisfy Border Force officers who last week decided Djokovic did not meet entry requirements.

After four days in detention, Djokovic won a first challenge against the visa decision on Monday and has been able to train at Melbourne Park in the days since; however, he will be returned to detention on Saturday morning in the Victoria state capital after immigration minister Alex Hawke cancelled the visa anew.

Murray said: "It's not a good situation. I'm not going to sit here and start kicking Novak while he's down. It's unfortunate it's ended up in this sort of situation.

"It's just one to get resolved. I think it would be good for everyone if that was the case. It seems like it's dragged on for quite a long time now.

"It's not great for tennis, not great for the Australian Open, not great for Novak, and a lot of people have criticised the government here as well, so it's not been good.

Murray banged his head against a microphone in exasperation as he faced another question on the matter, clearly by now sick of being asked about Djokovic.

The Scot, a former world number one and long-time friend and rival to Djokovic, was asked about the latest developments after coming off court, having just booked his place in the final of an ATP Tour event for the first time since 2019.

Speaking after his semi-final win at the Sydney Classic, Murray said: "I would encourage people to get vaccinated.

"But I do feel like people should be able to make their own decisions. Ultimately, people have to make their own choices, but there is also consequences sometimes for those decisions as well."

Former doubles world number one Rennae Stubbs told Australian broadcaster ABC she expected the story to keep rumbling on.

"It's not over, he's staying in the country, but for the ramifications for the Australian Open, it's huge," Stubbs said.

"It's hard to know, obviously I'm not in his mind, but I would say he's going to be extremely disappointed, very sad, angry. I think he's probably going through all the emotions you can imagine as a human being."

Before the hearing on Sunday was confirmed, Stubbs said: "Unfortunately for Novak, it's not looking good."

Djokovic has been drawn to face fellow Serbian Miomir Kecmanovic in the first round in a match that would be expected to take place on Monday or Tuesday.

Although the case of Djokovic has drawn global attention, Australian Stubbs said the single-minded nature of tennis players meant most were "really not concerned about Novak and his dilemmas".

"I think they're ready to get on with this tournament," she said. "I frankly think that most of them are sick and tired of talking about Novak and dealing with this situation in general."