Family of a Geelong teen who died in hospital days after being injured in a brawl outside a shopping centre have donated his organs.
Mohammad Mohammadi was stabbed through the heart on August 23 last year after an incident at Corio, in Geelong's north.
He underwent emergency surgery to repair significant injuries, but was declared brain dead. His life support was turned off just days after his 18th birthday.
Three teenagers, initially facing affray charges over the fight, were charged in June this year with Mr Mohammadi's murder.
Alith Wal and Nyal Mainyal, both 19, and a 17-year-old boy who cannot be identified, faced court in Geelong on Monday.
Members of Mr Mohammadi's family held each other and cried throughout an online hearing where medical experts discussed the teen's fatal injuries.
Forensic pathologist Sarah Parsons said the chest wound was likely caused by a single blade that went through Mr Mohammadi's rib cartilage, causing an injury to the right atrium and ventricle of his heart.
He also suffered a through-and-through injury to his upper leg and lacerations to his armpit.
While defence lawyers suggested there was no evidence of more than one application of force behind the chest wound, Dr Parsons said Mr Mohammadi had significant incisions from his surgery and organ donation.
She was unable to identify what sort of weapon might have caused the injuries because of surgical intervention and suturing of the wounds.
Mr Mohammadi's family donated a number of his organs after he was declared brain dead.
At the time of the autopsy none of the chest organs were in their usual position, meaning Dr Parsons could only give a "very approximate" suggestion about the depth of the wound.
"The appearance of the stab wound does suggest it's a single-edged weapon. Whether it's slightly serrated or a single bade, it could be either," she said.
Another doctor, Nickie Reid, said she examined Mr Mohammadi prior to the organ donation, but was also unable to give further detail about the type of blade that might have caused the injury because of the major surgical intervention.
She suggested the wounds to his armpits may have caused serious nerve damage to Mr Mohammadi's arm.
But he had been declared brain dead at that time, and movement and sensation cannot be assessed.
A committal hearing for the three teens is continuing.