It is not often that a leading world sports star is deported from a country where a major event is happening, but that is exactly the case with Novak Djokovic.
The world No. 1 travelled to Melbourne believing he had an exemption from the vaccination requirement to enter the country, only for Australian Border Force to cancel his visa upon arrival.
It's a story that has been brewing for weeks and can be a complicated follow, so here we run you through the full timeline of events and look at how on earth it came to this.
Australian Open announce vaccination policy
It followed what was a farcical 2021 tournament in which players had to complete a two-week quarantine period that was messy to say the least.
A single positive COVID case on the flight to Melbourne saw upwards of 70 players unable to practice or leave their rooms entirely, with a spate of related injuries following once the tournament started.
To avoid a repeat and to appease a government strict on public health protocols, Tennis Australia chief Craig Tiley agreed to the vaccination policy.
"Everyone on site - the fans, the staff and the players - will need to be vaccinated in order to participate in this year's Australian Open," Tiley said.
The spotlight immediately fell on Djokovic, who had refused to confirm his vaccination status.
"There has been a lot of speculation around Novak's position," Tiley added. "He has noted and said publicly that it is a private matter. We would love to see Novak here [but] he knows he has to be vaccinated in order to play."
'There is no loophole'
On December 9, and with Djokovic still refusing to publicly discuss his vaccination status or plans, Tiley appeared on Australian television with an update.
This was the first time an 'exemption' policy was suggested in any real detail.
"To be clear up front, no one can play the Australian Open unless they are vaccinated, on either a double dose of all the required vaccines or a single dose of Johnson & Johnson, which also is an approved vaccine," Tiley told ABC.
"The only condition at which, outside of being vaccinated, that you could compete is if you receive a medically approved exemption from Australian authorities, specifically against the very specific ATAGI guidelines.
"It's very clear - there's no loophole - and there's no condition of which you can play the Australian Open unless you meet that criteria."
ATP Cup withdrawal
With the Australian Open less than three weeks away, Djokovic fuelled speculation that he would not be defending his title after all.
The world No. 1, who is passionate about representing Serbia in team events and had done so at the Davis Cup just weeks earlier, announced he was pulling out of the ATP Cup in Sydney.
It is an event that Djokovic previously played as a key part of his Australian Open build-up, so his withdrawal looked significant.
The following day, he was videoed practicing in Spain with official Australian Open balls, suggesting he was still planning on playing the first Grand Slam of the year.
'Medical exemptions granted'
A few days later on January 3, Tiley gave a further update on the criteria required to play the Australian Open.
This was when he confirmed there would be unvaccinated players at the tournament but only after they had gone through a rigorous medical exemption application process first.
"Every athlete coming into Australia has to be vaccinated and show proof of that, or has to have made application from a medical exemption," Tiley explained.
"In the case of tennis players, that's far more rigorous than anyone coming into Australia applying for a medical exemption.
"There are two medical panels that assess any application, and they assess it in a blind way. They don't know who the applicant is.
"Against the guidelines, an exemption gets granted or not. The reason for granting the exemption remains private, between the panel and the applicant.
"We know of athletes that have applied for an exemption and in cases, it's been granted.
"Some of those (players) have indicated that they're here, but that's up to the athlete, to disclose and [decide] whether they want to share that information."
'I'm heading Down Under'
Sure enough, a day later, Djokovic posted a picture of himself departing for Australia on his social media channels.
An outcry followed from the Australian public and media. Australians have been hit hard by COVID restrictions and many felt preferential treatment had been given to Djokovic.
Some players were also seemingly unhappy, with Jamie Murray saying: "I mean, I don't know what to say about that really.
"I think if it was me that wasn't vaccinated, I wouldn't be getting an exemption."
Fellow Brit Liam Broady also seemed put out by the news, posting on social media: "The second AO announced there would be exemptions we all knew."
'Next plane home…'
Following the the Australian public and media's angry outcry at Djokovic's exemption, Aussie Prime Minister Scott Morrison felt the need to get involved.
For some analysts, this was a telling moment. There is an election coming up in Australia and many Djokovic supporters believe he is using the public outcry to make the Serbian political collateral in his re-election campaign.
"Any individual seeking to enter Australia must comply with our border requirements," Morrison said.
"He has to because if he's not vaccinated, he must provide acceptable proof that he cannot be vaccinated for medical reasons and to be able to access the same travel arrangements, as fully vaccinated travellers.
"So we await his presentation and what evidence he provides 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."
Detained at airport
Just as Morrison predicted, when Djokovic arrived in Australia he was not permitted to cross into the country.
Instead, he was detained in isolation while his documentation to validate his exemption was examined.
As the hours passed it soon became clear something major was happening. Five hours in, Djokovic's father Srdan took to Serbian television to call on people to "take the fight to the streets" if his son was not freed immediately.
Soon after, the Serbian President Aleksandar Vucic got involved, saying: "Just finished a phone conversation with Novak Djokovic.
"I told our Novak that the whole of Serbia is with him and that our bodies are doing everything to see that the harassment of the world's best tennis player is brought to an end as soon as possible.
"In accordance with all the norms of international public law, Serbia will fight for Novak Djokovic, for justice and truth. By the way, Novak is strong, as we all know him."
A few hours later, Australian Border Force confirmed what by then just about the whole world suspected.
"The Australian Border Force will continue to ensure that those who arrive at our border comply with our laws and entry requirements," an ABF statement read.
"The ABF can confirm that Mr Djokovic failed to provide appropriate evidence to meet the entry requirements to Australia, and his visa has been subsequently cancelled.
"Non-citizens who do not hold a valid visa on entry or who have had their visa cancelled will be detained and removed from Australia."
'Held captive' in immigration detention hotel and comparison to plight of Jesus
Djokovic used his right to appeal the decision and was escorted to the Park Hotel in Melbourne - an immigration detention hotel.
By now there were plenty others who'd had their say. Morrison again backed the decision to deport Djokovic, while health secretary Greg Hunt confirmed Djokovic had failed to provide sufficient proof of grounds for medical exemption.
Meanwhile, back in Belgrade, Djokovic's father Srdan was far from finished. He called a press conference at his restaurant and made some outlandish claims.
"Our Novak is being held captive," he raged. "Scott Morrison dared to attack Novak and expel him, but he did not even enter their country.
"They wanted to underestimate him and bring him to his knees, as well as our country. We are Serbs! We are a proud European, civilised nation.
"We never attacked anyone, we just defended ourselves! Novak does the same! With his behaviour and attitude, he shows what kind of people and what kind of country he comes from.
"We are proud of our Novak, our ideal, our light at the end of the tunnel. This is a political struggle!
"This has nothing to do with sports.
"[Novak] fulfilled all the conditions to enter, but he was not allowed to enter and win the Australian Open. People from the Western world who think the world is theirs are wrong!
"We are the majority world! We are part of the libertarian world! We are no less or more valuable than them! Novak has been showing with his works for 20 years that he is a part of the liberal world.
"Jesus was crucified, he endured and is still alive among us! In the same way, they try to crucify Novak and throw him to his knees."
Djokovic's mother, Dijana, also had her say, alleging that the hotel conditions are poor and his requests to be moved have been denied.
"I spoke with him a couple of hours ago, he was good, we didn't speak a lot but we spoke for a few minutes. He was trying to sleep, but he couldn't," she said.
"As a mother, what can I say, you can just imagine how I feel, I feel terrible since yesterday, the last 24 hours.
"They are keeping him like a prisoner, it's just not fair, it's not human. I hope he will stay strong as we are also trying, to give him some energy to keep going. I hope he will win.'
"His accommodation [is] terrible. It's just some small, immigration hotel, if it is a hotel at all. With bugs, it's all dirty, the food is terrible.
"They don't want to give him a chance to move to a better hotel or a rented house."
However, defenders of the Australian stance say he is merely being treated the same as anyone else who enters the country illegally and he is, essentially, free to take a flight out of Australia whenever he chooses.
He is still there, though, as he is choosing to remain in Melbourne while he appeals the decision in court.
It is also worth noting that many have come out in support of Djokovic. As well as his family and his millions of fans, former coach and Grand Slam legend Boris Becker and former Australian Open quarter-finalist Tennys Sandgren have very vocally backed him.
The Australian Home Office has flatly denied that Djokovic is 'a prisoner' in his hotel.
Speaking with ABC, minister Karen Andrews said "Mr. Djokovic is not being held captive in Australia.
"He is free to leave at any time that he chooses to do so and [Australian] Border Force (ABF) will actually facilitate that."
A costly misunderstanding?
As per reports in Australia, the most likely explanation appears to be that Djokovic was let down by Tiley and Tennis Australia.
Djokovic is reported to have received his medical exemption based on a claim that he had recovered from COVID within the last six weeks. If he had, it was certainly a well-kept secret. Djokovic tested positive in the summer of 2020 at the Adria Tour, but no reports have surfaced of an infection since.
That's not to say his claim was not legitimate, though. He is believed to have certification from a doctor in Serbia to that effect, although that was not deemed sufficient for Border Force under their criteria to enter the country.
Indeed, it is likely that the exemption Djokovic did receive was to play in the Australian Open without vaccination, not enter the country.
Two letters to Craig Tiley have emerged from the Australian Ministry for Health from as far back as November making it clear that a previous COVID infection would not circumvent the Federal vaccination requirement to enter the country.
That made the exemption granted to Djokovic by Tennis Australia or the Victoria regional government next to worthless with regards actually getting into Australia. All they would do would allow him to play without vaccination once he was there.
A document was subsequently leaked from Tennis Australia which informed players that tournemtn officials had 'clarified' with the Federal Government that a previous COVID vaccination would be sufficient to gain entry to the country.
This document, though, was dated after the letters clearly informing Tiley that the opposite was in fact true. Djokovic, then, was in possession of wholly inaccurate information.
It wasn't just Djokovic, either. Czech doubles player Renata Voracova was deported on the same grounds. She was in the country under the same invalid exemption Djokovic is claiming.
"The ABF can confirm that one individual has voluntarily departed Australia following ABF inquiries," the ABF said.
"We can also confirm that the visa of a third individual has been cancelled. This person has been taken into immigration detention pending their removal from Australia."
Tennis Australia, meanwhile, told the Sydney Herald and Sun that they completely reject suggestions that players were "knowingly misled".
Djokovic's request to appeal his deportation was not opposed, so he was allowed to remain in the immigration detention hotel until it was heard.
It was ultimately successful too, but more on a technicality than anything else.
Djokovic's defence team argued to Justice Anthony Kelly that the Serbian was not provided adequate time to respond to the cancellation of his visa when initially detained at the airport - and the judge agreed.
He was ordered to be released from detainment immediately and his visa reinstated, although the government responded immediately by saying they retained the right to use their own power to cancel it again, and the decision would be 'considered' by minster for immigration' Alex Hawke.
Ultimately, Djokovic argued that procedural practices were carried out in an 'unreasonable' way that did not give him a fair chance to resolve the issue.
Damaging revelations, admissions, and apologies
Following Djokovic's release from detainment, the media, freshly armed with the documents Djokovic submitted to court in his appeal, did their own sleuthing and uncovered a string of issues.
The date for Djokovic's Covid test and diagnosis was stated to be December 16, but he was pictured at an event with children on the 17 and a L'Equipe photoshoot on the 18, both without a face covering.
Additionally, Djokovic claimed on his travel declaration that he did not travel to any other countries for 14 days before his arrival in Australia. However, he was pictured in both Serbia and Spain in that period.
Djokovic responded and provided clarity, saying he did not have the result of his test before he met with the children, but admitted he kept his L'Equipe meeting despite knowing he was Covid positive.
The journalist who was interviewing said Djokovic rejected requests to remove his mask except for the photos themselves, but he also did not disclose he was infected with Covid-19 at the time of the interview.
Hawke then requested further documents from Djokovic's legal team as it became clear they were preparing for another attempt to deport him.
Visa cancelled for a second time
That attempt eventually materialised on the evening of the Friday before the Australian Open is due to start.
Advocates of Djokovic claimed it was a deliberate tactic to hamstring him legally, saying they timed it to prevent a well-prepared appeal.
The appeal still happened, though, with Djokovic's lawyers gaining an injunction preventing him from being deported until after his case had been heard.
A hearing was quickly scheduled for Friday night to prepare the orders upon which Djokovic would make his stand, with Justice Kelly again in the chair.
After setting the schedule, Kelly referred it to the Federal Court and the appeal will be heard on Sunday - the day before the Australian Open.
Shifting sands beneath Djokovic
It was always going to be a considerably more difficult case to win for Djokovic than the initial appeal, mainly because the defence team had been backed into a corner.
They were no longer be able to fight on the procedural grounds that were successful before with his case hinging instead on convincing three Federal judges the government had not aplied reason totheir decision.
That was always going to be tough given the wording in the section of the law itself, which says Hawke only needed to show his judgement 'maybe' had merit.
The State essentially claimed that leniency with Djokovic would undermine the Australian pro-vaccination message and risked fuelling an anti-vaccination movement in the country.
Perhaps predictably, the judicial review proved too tough a mountain for even Djokovic to climb.
His legal team had very few cards to play and claimed it was clear that Hawke had not fully considered his decision. They claimed deporting Djokovic, not allowing him to stay, would provoke more civil unrest based upon the reaction when his visa was initially cancelled.
They also tried to challenge the idea about whether or not Djokovic even was an 'anti-vaxxer,' pointing to the vaccine being available at the Serbia Open last season, which Djokovic helped organise.
However, the State countered both of those points, and repeatedly used the low threshold for justification to their favour.
They did not have to prove that Djokovic remaining in the country would provoke civil unrest. They simply had to present cause for believing it might.
The State also said that whilst the previous Covid-19 infection explained why Djokovic had not got vaccinated since December, the fact he also refused to get vaccinated before that proved he was anti-vaccination.
After two hours of deliberations, the judges returned a unanimous verdict to dismiss Djokovic's appeal, adding it was not in their remit to question the government's decision, only review the legality of it.
Djokovic them quickly released a statement, saying he would fully cooperate with officials and leave Australia.
"I'd like to make a brief statement to address the outcomes of today's Court hearing," Djokovic said.
"I will now be taking some time to rest and to recuperate, before making any further comments beyond this.
"I am extremely disappointed with the ruling to dismiss my application for judicial review of the decision to cancel my visa, which means I cannot stay in Australia and participate in the Australian Open.
"I respect the Court's ruling and I'll cooperate with the relevant authorities in relation to my departure from Australia.
"I am uncomfortable that the focus of the past weeks has been on me and I hope that we can all now focus on the game and tournament I love.
"I would like to wish the players, tournament officials, staff, volunteers and fans all the best for the tournament."