Hume Crime Investigation Unit detectives are appealing for public assistance after a man was assaulted at a supermarket in Moonee Ponds earlier this year.
Investigators have been told a man tried to leave a supermarket on Homer Street without paying for items when he was approached by staff around 9.40pm.
The man attacked the staff member punching and kneeing him to the head before fleeing the area.
The victim received serious head injuries requiring surgery.
The man is described as Caucasian in appearance, 30-45-years-old with a slim build.
Investigators have released an image of a man who may be able to assist with their enquiries.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000 or file a confidential report online at www.crimestoppersvic.com.au