Kaine Geoffrey Jones punched a man in the car park of a Central Coast shopping centre less than six months before he knocked out Graeme Wilton, Newcastle Local Court has heard.
Mr Jones, 23, was committed for trial to the NSW Supreme Court on Tuesday for one count of murder and one count of causing grievous bodily harm with intent.
He punched Mr Wilton once on the evening of December 12, 2013, before Mr Wilton's head struck the road rendering him unconscious, a police statement said.
Mr Jones allegedly got in his car, performed a burnout near Mr Wilton's motionless body lying in the middle of the road, and then drove off.
Mr Wilton regained consciousness, had no memory of the incident and was later placed in a coma.
He died in February 2014.
He had been on a two-year holiday around Australia with his wife when they checked into a caravan park at Mannering Park on the Central Coast on December 8.
Mr Wilton went for a walk on his own after 7.30pm on December 12.
Some witnesses told police they heard Mr Jones' car come to a screeching halt before they saw Mr Wilton bang his palms on the bonnet then raise his hands in the air.
At least one witness said they saw Mr Jones get out of the car and punch Mr Wilton once.
Mr Jones later told police Mr Wilton "ran out in front of the road, in the middle of the road and I tried to get around him but he side-stepped in front of me so I locked the car up and he slammed his hands down on the bonnet".
Mr Jones said Mr Wilton assaulted him before Mr Jones got out of the car and punched Mr Wilton.
The court heard from a number of witnesses who saw Mr Jones punch a man in the car park of Westfield Tuggerah in June 2013.
Mr Jones told police he was driving the wrong way down a one-way section of the car park when he threw a can of drink at another vehicle.
He said a passenger in the other vehicle got out of the car and approached him in an aggressive manner before Mr Jones threw two punches.
He said he stopped punching when he realised the other man was not throwing any punches.
The alleged victim told the court Mr Jones got out of his car and started throwing punches straight away.
Mr Jones did not enter pleas on Tuesday, but his barrister previously told the court he was acting in self defence in both cases.
Mr Jones will face the Supreme Court in September.
