A young Victorian man fatally struck a grandfather's head with a baseball bat over a misguided dispute in Melbourne's east, a crown prosecutor alleges.
Hudson Martin, 21, was one of eight young men who set upon Anthony Clark's Mooroolbark home shortly before 11pm on Christmas Day in 2019.
The group believed Mr Clark's relatives had assaulted one of their mothers earlier in the night during a dispute over some illegal fireworks, crown prosecutor Mark Gibson KC told the Supreme Court on Tuesday.
When the group arrived at Mr Clark's home, the grandfather threatened them with a baseball bat and ordered the males to leave his property.
From there, violence ensued and the prosecution alleges Martin used Mr Clark's baseball bat to strike the 50-year-old in the head.
He fell to the ground and was allegedly kicked in the head by one of the other males before the group fled.
The grandfather was conscious and breathing but incoherent when officers arrived.
He was taken to hospital where he died three days later from a significant traumatic brain injury.
Martin has pleaded not guilty to Mr Clark's manslaughter.
The 21-year-old told police he did hit Mr Clark with the bat because he was "petrified" and believed he would have been hurt if he didn't defend himself, the jury was told.
The prosecution will argue Martin was not acting in self-defence, Mr Gibson said.
It was instead a case of assault with Martin's bat strike the "substantial and operative cause" of Mr Clark's fatal brain injury, the prosecutor alleged.
Mr Gibson's opening trial address will continue on Wednesday afternoon, before defence counsel Ashlee Cannon delivers her opening remarks.
