Tennis plays on as lockdown halts A-League

Sydney FC's A-League clash against Western Utd in Melbourne has fallen victim to the COVID lockdown. (AAP)

The Australian Open will play on, without crowds, but Saturday's two A-League fixtures have been postponed due to Victoria's five-day COVID lockdown.

While the on-court action at Melbourne Park is set to continue during the statewide lockdown period, Western United's home match against Sydney FC at AAMI Park and Melbourne City's game with Western Sydney Wanderers at Bankwest Stadium have both been postponed.

Premier Daniel Andrews announced the snap statewide lockdown on Friday following a surge of cases of the virus, with stage-four restrictions to be in place across the state from 11.59pm on Friday until 11.59pm on Wednesday.

In a statement, Western United confirmed the decision to postpone their match with the Sky Blues, saying it was the only option from a health and safety perspective.

"We will remain flexible and ready to prepare for upcoming fixtures as advised," United chief executive Chris Pehlivanis said.

The club are waiting on Victorian government advice on whether an exemption for professional sport during the lockdown will allow the team to keep training.

As well as the two A-League fixtures, Saturday's W-League match between Newcastle and Melbourne City has also been postponed, with the Jets team to fly straight back to NSW on Friday after landing in Melbourne as the lockdown was announced.

Tuesday's A-League match between City and Sydney FC at AAMI Park is also under a cloud while similar doubts exist for Melbourne Victory's home game against Wellington Phoenix on Wednesday.

Elsewhere, the AFL is in a crisis meeting to determine what to do with this weekend's fixtures in the AFLW.

Supercars have postponed a planned test day in the Victorian town of Winton, moving that from Tuesday next week to Friday, February 19.

The NBL has two games scheduled in Victoria over the weekend with Melbourne United due to host Cairns on Saturday, and South East Melbourne Phoenix slated to play Perth on Sunday.

The inaugural NBL Cup, with all nine teams travelling to a Melbourne hub, is currently scheduled to start next Saturday.