It's been a hectic, dramatic and controversial run-up to the first Grand Slam of the year. Here's all you need to know about what's happened so far in preparation for the Australian Open.
Andy Murray is the latest big name to withdraw from the Australian Open. Although he wanted to play - and was given a wildcard as his ranking didn't entitle him to direct entry - he contracted coronavirus which prevented him from taking one of the charter flights to Melbourne, where all the other competitors are currently in quarantine. Despite discussions between his camp and Tennis Australia, they were unable to work out any arrangement which would have meant he could travel to Australia, quarantine for the mandatory two weeks, and then start the tournament.
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Roger Federer is also not there. He is thought to be not entirely fit yet, but some reports have indicated that the quarantine requirements swayed him - he did not want to quarantine by himself and leave his family behind, and nor did he want to make his family sit through a fortnight in a hotel room with no access to the outside world.
The big names are currently in Adelaide, preparing for an exhibition event next week called A Day At The Drive. That will feature Novak Djokovic, Rafael Nadal, Dominic Thiem, Serena Williams, Ashleigh Barty, Simona Halep and Naomi Osaka. With the exception of Barty, who's been in her native Australia and not travelled since the pandemic hit, these players are in what appears to be better hotel accommodation than their counterparts in Melbourne, and also have greater liberties and luxuries.
Tournament director Craig Tiley acknowledged that there was some truth in this, saying: "I get the feeling it is perceived as preferential treatment.
"But they're the top players in the world. My general rule is if you're at the top of the game, a Grand Slam champion, it's just the nature of the business. You are going to get a better deal."
Top shots from 2020 Australian Open
SO WHO'S IN MELBOURNE?
Pretty much everyone else. Despite Tiley's assertion that the Adelaide stars are "Grand Slam champions", there are plenty of Slam winners in Melbourne too, including Stan Wawrinka, Bianca Andreescu, Sloane Stephens, Petra Kvitova, Victoria Azarenka, Angelique Kerber, Iga Swiatek and Svetlana Kuznetsova.
Great Britain's Johanna Konta is also there, and is seeded 14th for the competition. In the absence of Murray and Kyle Edmund, Dan Evans leads the British men's charge.
Some players in Melbourne have been unimpressed with the cleanliness of their accommodation - but the state of Victoria's emergency services minister Lisa Neville has reminded them that if they want their rooms vacuumed or dusted, or their bed linen changed, they need to do it themselves.
And as for Yulia Putintseva's complaint about mice, Neville has hinted that there was food left out to attract the rodents - or "some feeding going on," as she put it.
“Every tennis player needs to clean their own room and change their own beds if they want that,” Neville said.
“We will keep doing pest control if we need to but hopefully that pest control work that was done this week will have fixed the problem.”
WHY ARE SOME PLAYERS ON COURT AND OTHERS NOT?
Most of the players in Melbourne are allowed out of their rooms to train for a couple of hours a day.
Some, however, are not. At least three of the charter flights bringing players to Melbourne also carried cases of coronavirus - and so all those travellers have had to go into so-called "hard quarantine", where they are not allowed out of their rooms at all.
Most of those players are taking it in good part. Great Britain's Heather Watson, for one, has been livening up her days with some funny videos - including this attempt at hotel-room triathlon.
Doubles star Edouard Roger-Vasselin set up this spectacular shot of the year so far.
Others are not quite so good natured. Vanessa Sierra, the girlfriend of Bernard Tomic, posted a video in which the player featured and the reality TV star complained about having to wash her own hair, make her own bed, and do her own dishes.
And Roberto Bautista Agut was caught on camera likening quarantine to "prison" - for which he later apologised.
HAVE ANY PLAYERS IN MELBOURNE TESTED POSITIVE WHILE IN QUARANTINE?
On January 20, the state health authority confirmed there had been seven positive tests for people connected to the tournament, with a further three currently under review and possibly linked to an old infection.
One of the positive tests belonged to Sylvain Bruneau, the coach of Bianca Andreescu, who posted an apology on social media, saying he was sorry for the impact he would have on everyone else on his flight.
Spain's Paula Badosa has also tested positive. She had previously complained vociferously on social media about having to quarantine, but has now apologised, writing: "Please, don’t get me wrong. Health will always come first and I feel grateful for being in Australia."
Some reports have suggested that three other players have also tested positive but they have not been named publicly.
WHAT HAS NOVAK DJOKOVIC SAID?
Novak Djokovic passed on some suggestions to Craig Tiley that he thought might make the players' quarantine in Melbourne more bearable.
Some of the requests were fairly reasonable, such as more fitness equipment in hotel rooms and improved food selections (although players do also have the option of ordering food in as well as eating from the menu provided).
Others were always bound to be rejected out of hand - such as reducing the number of days in quarantine, allowing players to meet up with their coaches, and possibly moving players from hotels to private houses with tennis courts.
State premier Daniel Andrews made it clear that no allowances would be made, no matter where the requests came from: "People are free to provide a list of demands. But the answer is no. I know that there's been a bit of chatter from a number of players about the rules. Well, the rules apply to them as they apply to everybody else, and they were all briefed on that before they came."
After a backlash from plenty of observers, including a lot of Australians who have put up with a tough lockdown for months in order to eradicate coronavirus, Djokovic issued a statement, in which he said:
Not every act is taken at its face value and at times when I see the aftermath of things, I do tend to ask myself if I should just sit back and enjoy my benefits instead of paying attention to other people's struggles. However, I always choose to do something and be of service despite the challenging consequences and misunderstandings.
Djokovic was also subject to severe censure after being spotted in the players' minibus without a mask, and was the subject of criticism last year, following his staging of the Adria Tour events in which a number of players - including himself - contracted the virus.
He's got one big name on his side, though - Eurosport expert Boris Becker, who's said the world number one was absolutely right to wade into the debate.
WHAT HAS NICK KYRGIOS SAID?
Nick Kyrgios spent much of 2020 sitting on the sidelines - like his compatriot Barty, he chose not to travel outside of Australia. Now that the tour has arrived in his native land, he isn't short of commentary on his peers' behaviour.
"Djokovic is a tool. I don’t mind Bernie but his Mrs obviously has no perspective, ridiculous scenes," he tweeted.
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