There is considerable doubt as to whether January's Australian Open can be staged in Melbourne as planned.

Tennis Australia had hoped they would be able to practice during the 14-day quarantine, before two weeks of action leading into the Australian Open.

Sources have since told BBC Sport that the state government's decision is unlikely to change.

However, players may be allowed into Australia at the very end of December.

This would potentially give them enough time to be ready to start the Australian Open qualifying event, as scheduled, on Tuesday, 12 January.

But that assumes players will be able to practice during their quarantine - something which is likely, but has not yet been signed off by the state authorities.

It may even still be possible for players to compete during the period of quarantine, as happened in New York in the run up to the US Open.

Another possibility is that the Australian Open may be pushed back by a week or two, to allow the warm-up events to go ahead as planned.

Tournament director Craig Tiley has openly discussed the possibility of delaying the tournament in the past.

There would be repercussions for the events that normally take place in early February, but the sport is extremely likely to prioritise the first Grand Slam of the year.

It may also be that the size of the draws are restricted, to reduce the number of people coming into the country.

There was no qualifying, for example, at September's US Open and there was no mixed doubles competition in either New York or at the French Open which followed.

Melbourne has reported no new cases of Covid-19 for 19 days, but a recent outbreak in Adelaide has alarmed those tasked with suppressing the virus.