Masks are back, both indoors and outdoors.
Exercise and shopping will be limited to five kilometres from a resident's home.
Supermarkets, food stores, petrol stations, pharmacies, bottle shops and banks will remain open.
Another 12 new cases were recorded overnight taking the total to 26 cases.
"As of first thing this morning, we have identified in excess of 10,000 primary and secondary contacts who will need to either quarantine, or test and isolate, and that number will continue to grow and change".
This time around, the problem appears to be with contact tracing.
Victoria has also expanded vaccination eligibility from today to people aged 40-49.
Hipkins said everything would be done to make sure those impacted by today's legal notification would be notified.
"While most services in and out of Melbourne today are operating as normal, we are adjusting our forward schedule to better reflect changing travel demand and booking trends".
On Wednesday, the federal government pledged to send an extra 140,000 doses of the AstraZeneca vaccine to Melbourne to boost protection of elderly and other vulnerable groups.
Richmond's contingent already planned to be tested for COVID-19 as a precautionary measure to assist the Crows in returning to South Australia after the match.
A report released on Wednesday in SA found it likely he caught the virus through aerosol transmission due to the "timing of doors opening and closing" at an adjacent room occupied by an infected guest.
Prior to the lockdown, Victoria had on Tuesday at 6 p.m. reinstated restrictions in response to the Whittlesea outbreak.
Private and public gatherings will be barred with the exception of intimate partners.
The state government and health authorities were reportedly considering a five-day "circuit breaker".
Authorities believe the circuit breaker lockdown is the only way to break the cycle of infections.
It is the fourth time the state has been placed in a lockdown.
That lengthy lockdown had subjected Victorians to a "living hell", Liberal Democrats MP David Limbrick State told Victoria's Parliament in September 2020.
Anybody who had been in one of the locations of interest in Victoria couldn't travel to NZ for at least 14 days after they had been at the location, Hipkins said.
Others described accounts of a grandmother who was banned from visiting her first grandchild, a child who had stopped talking, people so depressed they can not leave their houses, a schoolchild so depressed they refused to eat, and a woman afraid that her son was a suicide risk.
"We're going to monitor the situation in Victoria".
The AFL said thousands of fans who sat near the positive case were now required to self-isolate until they received a negative test, while health officials were reviewing CCTV to determine if others had been at risk.
In Perth, testing is being imposed on Victorian arrivals.