POLICE believe CCTV footage might hold the key to catching the killer of a man felled by a single punch outside a city nightclub more than five years ago.
Shannon McCormack was celebrating a Collingwood football victory with friends on May 27, 2007, when he was caught up in an altercation.
CCTV: Is this the man who king-hit Shannon McCormack?
Almost six years since Shannon McCormack, 22, died after being bashed outside a CBD nightclub, and CCTV released exclusively to The Age has seen a break in the case.
The 22-year-old was punched once, hit his head on the footpath and died in hospital after a week in a coma.
His father, Bill, has been campaigning for five years to find his son's killer.
Despite the police investigation and regular appeals for public help, the killer has never been found. There is a $100,000 reward for information leading to his identification.
Detective Sergeant Brent Fisher of the homicide squad said the man caught on CCTV footage outside Southbank's Queensbridge Hotel – near where Mr McCormack was punched – resembled a description that witnesses gave of his attacker. The man police want to talk to is between 165 and 175 centimetres tall, of thin to medium build and had light brown or blond spiky hair. He is believed to have been wearing a light purple or blue T-shirt and light-blue jeans.
The vision, provided to Fairfax Media, was sifted from more than 150 hours of CCTV footage and was taken around 40 minutes before Mr McCormack was punched, about 4am.
It shows five young men talking outside the nightclub. The man police want to identify then walks past, before one of the group of men – who he seems to know – stops him and shakes hands with him. They talk briefly before a third man joins the conversation. The men then all walk off together.
Mr McCormack was with friends of his younger brother – including two girls – when an argument broke out with three men. At an inquest, one of the girls said they were harassed by the men, and the male friend of Mr McCormack's brother remonstrated with them. Mr McCormack stepped in to break up the fight, then one of the three men walked away, turned, ran back and hit him. Mr McCormack's head hit the footpath and a wall.
Mr McCormack regained consciousness and went home, but was later taken to the Austin Hospital, where he lapsed into a coma and later died.
Shannon McCormack's father reflects on CCTV
Bill McCormack says a man that has been newly-noticed by police in CCTV, matches witness descriptions of the person who king-hit his son outside a CBD nightclub, ultimately killing him.
Detective Sergeant Fisher said relationships changed over time, and people who were with the man who punched Mr McCormack might now be willing to talk to police. It was also possible that they did not know what happened that night.
''You'd think with all the media response at the time that they might have some knowledge, but there was no ambulance called, no police, so you never know,'' Detective Sergeant Fisher said.
The head of the homicide squad, Detective Inspector John Potter, urged anyone who recognised any of the men in the footage to contact police.
''Someone out there knows what happened to Shannon,'' Detective Inspector Potter said.
''No one should go out for a good time with friends and never make it home.
''If you are aware of any information about what happened to Shannon, please call us and help provide the McCormack family with some sort of closure to their grief.''
The possible breakthrough comes a month after Templestowe man David Cassai was punched in the head outside shops at Rye and died shortly afterwards in hospital.
CCTV footage of the incident was used to identify Dylan John Closter, 18, who has been charged with manslaughter.