Mr Andrews said he was pleased the daily numbers were not increasing day-on-day.

"It's always challenging to analyse any one day's results. You'd like to see numbers coming down at the end of the day, though we're not seeing the doubling and doubling again," he said.

"So what that says to me ... is that the sorts of measures we've put in place are having a direct impact."

More than 29,000 tests were conducted yesterday.

Mr Andrews said it was too early to discuss whether restrictions needed to be hardened. Victoria entered stage three restrictions almost two weeks ago, on July 9.

The Premier said it could take days after the two-week mark to see numbers fall, due to the time lag in receiving test results.

"Tomorrow does mark the first two-week period of a six-week lockdown," he said.

"It's too early for us to be talking about next steps. It's too early for us to be, I think trying to be definitive about what the third week and the fourth week look like. This is very fast-moving."

From Thursday, Victorians in lockdown areas will be required to wear masks.

Mr Andrews welcomed the federal government’s extension of JobKeeper and JobSeeker and flagged additional state stimulus.

Prime Minister Scott Morrison announced on Tuesday morning the government would cut the JobKeeper wage subsidy to $1200 a fortnight for full-time workers and $750 for part-time workers, down from the current rate of $1500 for both.

The Victorian budget later this year would include financial boosts for both individuals and businesses, he said.

He applauded the federal government for tailoring its wage subsidy to target those in hard-hit industries.

"The commitment … was always that hardship would drive the Commonwealth government's response and it seems from the reporting, and I'll let the Prime Minister obviously make the detailed announcements, but it would seem that he's been true to his word," Mr Andrews said.

The wage subsidies would be a feature of the response to the pandemic for many months to come, he said.

Chief Health Officer Brett Sutton said case numbers had plateaued and the lockdown restrictions were having a positive effect.

The state’s modelling of case numbers from two weeks ago suggested daily case numbers could be in the thousands each day by this point in time, he said.

He said there had been more pronounced reductions in case numbers in hotspots locked down prior to the metropolitan-wide lockdown.

"Certainly we're seeing a roller coaster of numbers," he said.

"There has been some levelling in the last four or five days, and I know that day-to-day changes can be substantial.

"But the modelling of a couple of weeks ago, if we had been on an exponential curve … would have been thousands of cases at this point in time and we're on 374. I'm not satisfied with that, but it's much better than 1000."

Meanwhile, Health Minister Jenny Mikakos said the state's contact-tracing system had been bolstered by additions from the Australian Defence Force and other places, and now includes 2000 full-time tracers.