Barbarich pinned down Hancock and grabbed his upper body in a bear hug as he bit his ear. He then yanked his head back, tearing off the top part of the ear before getting off the victim and walking away.
Hancock was taken to hospital, his ear bleeding profusely. The severed piece of ear was not reattached.
Two days later, Hancock, his father and another young man drove to Fawcett St to exact revenge on Barbarich. He was in a car, which his girlfriend was backing out of a driveway, and the three assailants rammed the side before getting out and attacking it, with a sledgehammer, sticks and a log splitter. A knife was also used.
The young woman was removed and the three men repeatedly struck Barbarich about the head. Trapped in the car, he was unable to avoid the blows. He suffered a fractured skull and one of his ears was almost severed.
The attack resulted in charges against Dylan Hancock, his father Kevin Allan Hancock, 46, and 21-year-old Gavin Manu Howie.
Kevin Hancock, the first of the trio to plead, was last September sentenced to seven and a-half years in jail.
Gavin Howie was last December sentenced to two years in jail.
Dylan Hancock was last month given three years and 11 months in jail for injuring Barbarich with intent to cause grievous bodily harm.
At yesterday's sentencing, Crown counsel Richard Smith said Barbarich had "an unenviable record" of offending.
Defence counsel Bernadette Farnan said the entire incident, especially the brutal beating to which he was subjected, had brought home to Barbarich the consequences of violence.
Judge Crosbie said the injury Barbarich caused to Dylan Hancock was a serious and singular event and had resulted in three other men retaliating.
It was obvious he and Dylan Hancock had been drinking and things got out of hand but there was a need to say to Barbarich "enough is enough".
Despite his age, he had been assessed by a psychologist as a violent man, with 11 previous convictions for violence. Incarceration was required to protect the public.