Novak Djokovic’s participation at the Australian Open is under fresh doubt after the Victorian government said it would not support his visa application.

Djokovic looked primed to defend his title after Tennis Australia granted him medical exemption from Covid-19 vaccination rules, which sparked public outrage in Melbourne, whose residents have been hit hard by restrictions throughout the pandemic.

Australia’s Prime Minister Scott Morrison warned the world number one, who has previously spoken out against vaccinations, would be on the “next plane home” if he could not provide “acceptable proof” that his exemption was legitimate.

The Serbian arrived in Melbourne on Wednesday evening local time, but faced trouble at the border, with Acting Sports Minister Jaala Pulford confirming that the state government was not supporting his visa application to compete in the Australian Open.

She tweeted: “The Federal Government has asked if we will support Novak Djokovic’s visa application to enter Australia.

“We will not be providing Novak Djokovic with individual visa application support to participate in the 2022 Australian Open Grand Slam.

“We’ve always been clear on two points: visa approvals are a matter for the Federal Government, and medical exemptions are a matter for doctors.”

It remains unclear whether Djokovic was allowed into the country and the situation was still developing late into the night in Melbourne.

Tournament director Craig Tiley earlier said it would be “helpful” for Djokovic to clarify his situation on what exempts him from vaccination.

Prime Minister Morrison told a media conference on Wednesday: “We await his presentation and what evidence he provides us to support that.

“If that evidence is insufficient, then he won’t be treated any different to anyone else and he’ll be on the next plane home.

“There should be no special rules for Novak Djokovic at all. None whatsoever.”

More than 90 per cent of Australia’s over-16 population are fully vaccinated.

Morrison’s comments were echoed by a statement from Australia’s minister for home affairs Karen Andrews.

“Australian Border Force will continue to ensure that those who arrive at our border comply with our strict border requirements,” her statement read.

“No individual competing at the Australian Open will be afforded any special treatment.”

The Australian Open is scheduled to begin on January 17.

Tiley had earlier revealed 26 unvaccinated players applied for exemption, with Djokovic among only a “handful” given the green light under guidelines set by federal regulators.

Having insisted the 20-time grand slam winner had not benefited from “special favour”, Tiley later urged the player to be transparent on the issue as public criticism increased.

“We completely understand and empathise that some would have been upset by the fact that Novak Djokovic has come in because of his statements around vaccination in the past couple of years,” Tiley told reporters.

“We would love… Novak to talk about it and help us with it, but ultimately it’s going to be up to him.

“We aren’t in a position, even legally, to disclose other people’s medical information.”

Criteria listed by the Australian Technical Advisory Group as permissible reasons for a medical exemption range from acute major medical conditions to any serious adverse event attributed to a previous dose of Covid-19 vaccine.

A possible explanation is that Djokovic has contracted coronavirus for a second time at some point in the past six months, having previously caught it during his much-criticised Adria Tour event in Belgrade in 2020.

That would negate the need for vaccination, according to rules published last year by one of two independent medical panels involved in the decision.

The build-up to the season’s first grand slam has been dominated by whether Djokovic would be involved.

Speculation was heightened after he pulled out of the Serbia team competing at the ATP Cup in Sydney without explanation.

On Tuesday, the 34-year-old Serbian posted on Instagram that he was “heading Down Under with an exemption permission”.

The news was later confirmed in a statement from the Australian Open.

The tournament provides Djokovic with another chance to move clear of rivals Roger Federer and Rafael Nadal, with the three having each won 20 grand slam titles.

He was challenging for the calendar year grand slam in 2021 but fell short in the US Open final by losing to Daniil Medvedev, the man he beat in last year’s Australian Open final.