Premier Daniel Andrews is confident Victoria will get on top of its latest COVID-19 outbreak, though authorities remain concerned about "fleeting transmission" of the virus between strangers.
Victoria recorded 10 new COVID-19 cases on Friday, the first day of a statewide five-day lockdown, including four infections previously reported.
There are now 24 cases associated with the outbreak, which originated in NSW.
The new cases include a man in his 20s from Point Cook, who attended an AFL match between Carlton and Geelong at the MCG on Saturday and was seated in the MCC Members' Reserve.
He is the fourth person to have contracted the virus from an Ariele Apartments resident, who attended the match with a friend from Barwon Heads.
The infected man unknowingly contracted the virus from a group of NSW removalists who had worked at the Maribyrnong apartment complex late last week.
He passed the virus on to his parents and his friend, a teacher at Bacchus Marsh Grammar.
The four men at the MCG who contracted the virus were not seated near the infected man, nor were they known to each other.
Victoria's COVID-19 Commander Jeroen Weimar said transmission most likely occurred when the infected man went to the bar or the toilet.
"It's during those circulation movements that transmission occurred, and again we're back in the world of very fleeting transmission," he told reporters on Friday.
The entire MCC Members' Reserve has now been listed as a tier-one exposure site, while anyone who attended the Percy Beames Bar on Level 2 at certain times during the match will have to isolate until July 24.
Another two new cases are linked to the Young and Jacksons pub in the CBD, which the infected man visited prior to the match.
The two cases - a Richmond man and a member of the defence force based at HMAS Cerberus - are again strangers to the infected man and each other.
Mr Andrews said the cases proved the highly infectious nature of the Delta variant.
"Last year was a lot about mystery cases. Now it is about fleeting transmission, people who don't know each other, don't even register that they were in the same space together," he said.
Two further new cases are staff at Bacchus Marsh Grammar.
The school has reported another two teachers have tested positive, though the cases were not confirmed by the health department and could be included in Saturday's tally.
Mr Andrews said the state was dealing with 126 exposure sites including the MCG and public transport, with 1500 primary close contacts and 5000 secondary contacts self-isolating.
But the premier is adamant Victoria will "crush" the outbreak.
"I am absolutely certain that Victorians will rise to the challenge as we have done before. We will get ahead of this," Mr Andrews said.
Victorians who have lost work due to the lockdown will be eligible for weekly payments, jointly funded by the state and Commonwealth governments.
Some 90,000 businesses and sole traders that received support during the fourth lockdown last month will be automatically eligible for state government payments of $2000 or $3000.
The rules applied during last month's lockdown were reimposed overnight, including the five reasons to leave home, a 5km travel limit for exercise and shopping and compulsory mask-wearing indoors and outdoors.
All commercial furniture removalists have also been banned from entering Victoria for two weeks.
Transport workers travelling into Victoria from red zones will be required to get a COVID-19 test every three days instead of seven.
Also on Friday, Queensland authorities declared all of Victoria a COVID-19 hotspot starting from Saturday.
Anyone who has been to Victoria will be banned from entering Queensland except for returning residents and people who have a special exemption - and they will have to undergo 14 days of hotel quarantine.
Victorian locations where there is a risk you may have been exposed to COVID-19: https://www.coronavirus.vic.gov.au/exposure-sites
Australian Associated Press