The tennis season was halted in early March due to the spread of the novel coronavirus, which has infected more than 3.68 million people around the world while killing over 256,000, according to a Reuters tally.
The Australian Open was able to take place in January as scheduled but French Open organisers have moved the clay-court major back to September from its May start while Wimbledon has been cancelled.
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The fate of the US Open in New York is expected to be decided next month.
Tennis Australia Chief Executive Tiley said next year's Australian Open (AO) would not escape the impact of the pandemic.
"Worst-case scenario is no AO," he told the media.
"Our best-case scenario at this point is having an AO with players that we can get in here with quarantining techniques and Australian-only fans."

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Australia has had less than 7,000 confirmed cases of the novel coronavirus. Fewer than 1,000 people are still sick, though 96 people have died from the virus.
The country is expected to announce on Friday a loosening of social distancing restrictions with curbs on most businesses removed by July.
The men's ATP Tour and the WTA, which runs the women's circuit, have suspended all tournaments at least until mid-July after countries started locking down borders to contain the spread of the coronavirus.
Some players, both current and past, have said they fear the remainder of the 2020 season could be wiped out. Tiley has previously said he expected tennis to lose the remainder of the season to the pandemic.
"There's four scenarios and we've modelled everything," he said on Wednesday. "We've modelled the times we have to make decisions, dates we have to make decisions, who it impacts, how it's going to impact them.
"We've done that for 670 staff. We've done that for all of our partners -- our media partners, our sponsors and for all the governments and places we rent facilities.
"And now we're working on the international playing group and getting them to understand what each of those scenarios are and what it means for them and how we can action it."
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