Victoria has recorded 11 new coronavirus cases and no deaths for the third time in a week.
The state's death toll remains at 809 and the national figure is 897.
The number of active Victorian cases is 195 and Premier Daniel Andrews said on Friday it is the first time since June 26 that it has been below 200.
Of the new cases, six are linked to complex cases.
One is linked to the Chadstone cluster, taking that outbreak to 32 cases.
It has spread to suburban Frankston and also Kilmore, north of Melbourne.
"They are challenging, but we are throwing absolutely everything at them," said the state's Chief Health Officer Brett Sutton.
"We will get on top of these outbreaks, we always do.
"It is, of course, frustrating to see that slow, even if steady movement, down (in case numbers).
"We have seen a bit of a plateauing in recent days and I am as frustrated as anyone but the underlying trend will get us there."
Asked if he trusted the state's contact-tracing system, Professor Sutton replied on Friday "yes, I do".
Kilmore residents have spoken of inconsistent advice from health authorities as they manage the town's cluster.
"I accept that there will always be gaps and things that we need to tighten up, things that we need to review because there is feedback about what isn't working," Prof Sutton said.
"Any community member who speaks of the difficulties or the mixed messages or the inconsistencies is a lesson for us."
Professor Sutton said 679 people had been tested in Kilmore over the last three days.
The Frankston cluster has 12 cases and seven of them are active.
Professor Sutton also confirmed an outbreak at Box Hill Hospital in Melbourne's east had grown to four cases.
He added staff at the hospital are being tested, but could not say how the outbreak started.
Box Hill was also the site of an outbreak in mid-July.
The new cases, confirmed by the Department of Health and Human Services on Friday, bring Melbourne's 14-day case average to 9.4, a slight drop from 9.7 on Thursday.
Twelve mystery cases have been recorded between September 23 and October 6.
The city needs a 14-day average of five cases, and no more than five mystery cases during the same period, to further ease restrictions on October 19.
Premier Daniel Andrews said on Thursday it is "highly unlikely that nothing will change" come October 19.
"There will be some changes, the exact nature of those changes we will need to look at," he said.
The Kilmore cluster began when a person infected with COVID-19 linked to the Chadstone outbreak dined at the town's Oddfellows Cafe, in a breach of restrictions, on September 30.
More than 200 people who visited the cafe between September 30 and October 3 are self-isolating after a staff member contracted the virus.
Meanwhile, former health minister Jenny Mikakos has told the state's hotel quarantine inquiry that Mr Andrews' evidence about private security should be "treated with caution".
In her response to the inquiry's closing submissions, Ms Mikakos said it is "implausible" to suggest no one made the decision to use private security guards in the botched program.
Ms Mikakos resigned the day after Mr Andrews told the inquiry he held her accountable for the program, which has been blamed for the state's devastating second wave of coronavirus.
Also on Friday, Mr Andrews said the government had ordered an extra 1.2 million face masks.
On Sunday, Victoria's rules on masks will tighten and people can no longer substitute them with scarves or face shields.
