The victim was out with friends when he was knocked unconscious by a punch to the side of the head from the alleged attacker at 2am on July 9.
In a Ten 7 Aotearoa video posted by police, Sergeant Sam Oram said the victim had no interaction with the man before the assault, and was lucky to be alive.
The victim had been making his way down the mall, play-fighting with a friend, when the suspect began to follow them.
The suspect then approached the victim from the side and punched him in the head.
"I could feel my head smash on the concrete ... it’s just scary because I couldn’t really remember it," the victim said in the video.
The victim’s friends attempted to intervene to prevent the suspect leaving and there was an altercation, he said.
The suspect was then captured by CCTV footage running up Ballarat Mall, along Camp St and down Shotover St.
He is described as a European male, possible in his early 20s, wearing a black jacket, baggy blue jeans and white Nike shoes.
"I know that family or friends, or even an ex-teacher, will know who he is and we are asking for them to come forward.
"If we don’t catch up with this male he is going to go on and cause someone some serious harm," Sgt Oram said.
The victim, who was concussed, said he was hesitant to return to town in case a similar situation occurred, and if the police caught the person responsible it would be a relief for him and his family.
■ Police: 0800107-INFO.
