A youth justice worker has been assaulted at the new Cherry Creek facility.
The worker was reportedly punched in the head on Monday at the facility near Little River, after telling a young person not to wear slides in the kitchen area.
Another detainee came in and allegedly continued the attack, according to a report in the Herald Sun.
The worker remains in hospital, while union officials have inspected the site after the assault.
Detainees started arriving at the centre last week.