'Crunch time': Australian Open officials facing billion-dollar blow

D-Day looms as Australian Open officials try to lock in the biggest and richest event on the country's annual sporting calendar.

It's less than a month until the traditional start to the annual summer of tennis with the Open wildcard playoff, yet the billion-dollar Melbourne Park major remains in doubt.

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Needing special approval for a training bubble to be established to allow the world's elite players to prepare for the grand slam grind while in quarantine, Open chief Craig Tiley is desperately hoping for the government to come to the party.

"We're getting to crunch time now. We need commitments from the governments and the health officers," Tiley told AAP last month.

"If a player has to quarantine and be stuck in a hotel for two weeks just before their season, that won't happen."

Tennis Australia is working feverishly behind the scenes with the federal and state governments and the planned re-opening of state borders and 13 straight days without a new COVID-19 case in Victoria is a major boost.

But with most of the 2500 Open players and their entourages needing to travel from Europe and the USA, where coronavirus remains out of control, planning for the event remains a logistical nightmare.

Time is running out for the governments to commit to helping the Open from proceeding as scheduled from January 18-31.

Heat is on for Australian Open officials

The ATP Cup teams' tournament planned once again for Sydney, Brisbane and Perth is pencilled in to start on January 1, with Tiley sweating on the reopening of state borders for the multi-city event to go ahead.

With international players required to quarantine for 14 days, the likes of Novak Djokovic, Rafael Nadal, Roger Federer, fellow 39-year-old superstar Serena Williams and newly-crowned US Open champions Naomi Osaka and Dominic Thiem have just five weeks before boarding flights to Australia.

Yet confirmation of the 2021 Open being staged is still to be made.

If TA gets the green light, Tiley is pushing to have at least 25 per cent crowd capacity, meaning around 200,000 spectators can file through the Melbourne Park gates.

"The Australian Open in January will pump millions of dollars directly into the economy for Melbourne and Victoria and play a major role in accelerating the economic recovery in the state," he said.

"We can help the Victorian government, we can help the other governments but we need help too.

"We need exemptions on bringing in 2500 people."