Serena Williams is predicting a “rough few days” at the Australian Open with no crowds and players in a bubble as Victoria undergoes a snap five-day hard lockdown after an outbreak of COVID-19 cases.

But the seven-time Open champion supports the restrictions put in place from Saturday until next Wednesday.

“It’s rough - it’s going to be a rough few days for I think everyone, but we’ll hopefully get through it,” Williams said after her third-round victory on Friday.

“But, you know what, at the end of the day we have to do what’s best.

“Hopefully it will be all right.”

Williams said she’d enjoyed playing in front of crowds for the first time in almost a year at Melbourne Park, with her next match against Aryna Sabalenka now to take place in a mostly-empty venue.

“It’s not ideal - it’s been really fun to have the crowd back, especially here.

“It’s been really cool.”

Tournament boss Craig Tiley said cancelling the rest of the Open was never an option and the absence of crowds and a player bubble was one of the contingency plans that they already had ready.

The Open is close to the halfway point, with some players already through to the fourth round, and its due to conclude on Sunday, February 21 with the finals of the mixed doubles and men’s singles.

“Play will continue and players will compete in a bubble form not dissimilar to what they’ve been doing right throughout the year,” Tiley said.

“Those who will be allowed on site will be players and their direct support teams as well as those staff members who are unable to do their work from home.”

He said the new arrangement had been well-received by players, who he had met with over zoom and in person.

Tiley expected players to spend the bulk of their time on site, either playing or training, and they would otherwise remain under the same conditions as the general public.

Victorian premier Dan Andrews said tennis players were not considered “essential workers” but the nature of their profession meant they could not work from home.

“If you can work from home, you must,” Andrews said.

“That’s (Melbourne Park) their workplace.”

Andrews said the current infection - of the highly-contagious UK variant of the virus - was not linked to the tennis and there was no advice to call it off.

“I don’t have advice to cancel the event on the basis that it is unsafe, I just don’t have that,” he said.

“This case has got nothing to do with that event. This case is a different matter.”

The event has already suffered a significant financial hit with crowd limits reduced to 50 per cent capacity and Tiley conceded it would do more damage to their bottom line.

Just 76,213 fans attended in the first four days compared to a record 299,156 at the same point in 2020.

With a number of high-profile matches scheduled for Friday night, including Nick Kyrgios versus Dominic Thiem, Andrews urged people to “use good judgement” and not go out.

Tiley said he would leave it up to fans but they could get a refund if they chose not to attend, while tickets for the next five days would be refunded.