THREE days before Sunshine Coast teenager Cole Miller allegedly suffered a single blow that killed him, another man - this time in Canberra - was knocked unconscious, falling hard on concrete.
The blood-curdling video caught by CCTV cameras on New Year's Day and released by police appears to show two men having a heated confrontation, when a third man throws a punch from the side.
The victim goes limp, falling to the ground. He would later require emergency surgery.
The one throwing the "coward punch" is still at large, according to police.
He is described as being between 5'6" and 5'11 inches tall (170cm to 180cm) with dark complexion. He was wearing a grey T-shirt and black pants.
In a statement released on Friday morning, Police believe the man was struck about 2.45am outside a convenience store.
When police arrived, the victim was found "laying on his back unconscious with his head on the ground".
Police are asking anyone with information to contact Crime Stoppers on 1800 333 000.
Just days later, the 18-year-old Mr Miller would be attacked in Brisbane's Fortitude Valley. He was pronounced dead from his injuries the following day.
Two 21-year-old men - Armstrong Renata and Daniel Maxwell - have been charged with unlawful striking causing death in relation to the attack. The crime is designed to target those who throw a single fatal punch and carries a maximum penalty of life in prison.
The teen's death has prompted an enormous outpouring of grief across the Sunshine Coast and throughout Australia, with calls to crack down on alcohol-fuelled violence and those who throw the so-called "coward punches".
Mr Miller's funeral will be held on Wednesday at Brisbane's St Stephen's Cathedral.
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