Victoria has recorded 514 new local COVID-19 cases, with 366 of those currently classed as mystery cases.
In better news, there were no deaths recorded.
Of the 514 new cases, 148 have been linked, meaning 366 are currently mystery cases.
There were 41,758 vaccinations administered and 61,961 tests received on Tuesday.
Details and locations of the cases will be revealed later today, with the daily press conference normally held about midday.
It is expected that Ballarat's case numbers will continue to grow.
As of yesterday there were four active cases in Ballarat, but that number will likely climb today.
See where all the exposure sites are here.
Chief Health Officer Brett Sutton said the planned seven-day lockdown would give Ballarat "the best chance of opening up again in the shortest time possible".
In stark contrast, the city of Shepparton has come out of lockdown after a local outbreak of the Delta variant was brought under control.
Professor Sutton said modelling indicated the state's outbreak had not peaked and daily infections could rise to 1000.
"We have to press on with vaccinations at the fastest possible rate," Prof Sutton said.
With 68.3 per cent of eligible Victorians vaccinated, Mr Andrews said the state was on track to hit 70 per cent on Thursday.
See the location of all the active cases here.
The government has pledged to give Melburnians more freedoms, including an extra hour of exercise and an expanded travel limit, once 70 per cent of those eligible have received their first dose.
This was initially forecast to happen on September 23, but the state's soaring vaccination rate has brought the date forward.
Mr Andrews foreshadowed some rules might be relaxed as early as Thursday night but also raised the prospect they could be "rolled into" Sunday's roadmap announcement, which will outline the state's restrictions through to November.
Meanwhile, public transport to and from Melbourne's CBD will be suspended for six hours on Saturday to thwart an anti-lockdown protest.