BRIMBANK Crime Investigation Unit detectives are investigating an assault which occurred outside a hotel in Durham Road on Friday 20 September.
A 34-year-old Sunshine man is in intensive care in The Alfred hospital with life threatening injuries.
The man and his girlfriend were in the public bar when he was asked to leave by security staff.
It is alleged the man refused to leave and became involved in a scuffle with security before being ejected from the hotel.
While standing on the street with his girlfriend another unknown man approached the pair and a verbal argument took place between the two men.
During the argument the unknown man punched the victim in the head, causing him to fall backwards, striking his head on the footpath and rendering him unconscious.
Investigators are urging anyone with information to contact Crime Stoppers on 1800 333 000 or visit website www.crimestoppers.com.au