Anthony Georgiou cried for help and gasped for air after being placed into a headlock by two security officers at a Bunnings Warehouse.
He had stolen a gas cylinder and saw blade from the Frankston, Melbourne, store and the officers were trying to stop him from getting away.
"Help me, help me, let me go," a witness heard Mr Georgiou scream, as he struggled with them on the ground.
Despite his clear distress, the store's sub-contracted loss prevention officers (LPOs) continued to restrain the 31-year-old. He became unconscious and was taken to hospital, where he died later that day.
A Victorian coroner has found Mr Georgiou's September 2016 death would not have occurred if he was not restrained by the officers at Bunnings.
"There seems little doubt that had Mr Georgiou not been involved in the struggle ... he would have walked away from Bunnings that day," coroner Darren Bracken said in his findings, released on Tuesday.
Forensic pathologist Heinrich Bouwer, who conducted Mr Georgiou's autopsy, found his death was caused by complications with methylamphetamine use in a setting of physical restraint.
He told an inquest being put in a headlock at Bunnings had caused injuries that inhibited Mr Georgiou's breathing.
The security officers told the inquest they initially tried to get Mr Georgiou to take the stolen property back to the store, but he became aggressive and said "no f*** off" and walked away from them.
One of the officers said he grabbed Mr Georgiou, near the exit, told him he was under arrest and said "let's make it easy and come back with us", but he was ignored.
He tried to grab Mr Georgiou across the chest and placed his leg behind him to get him to the ground but he was "so strong that when I grabbed him he lifted me up".
The two officers said they used their force try and get him to the ground by putting him into a headlock, which violated Bunnings' code of conduct and training given to LPOs on how to deal with thieves.
But the coroner found the pair were never given a copy of the code and neither of them had attended training.
The store's manager witnessed the struggle but did not intervene. He told the inquest Bunnings told him not to get involved with LPOs when they were dealing with stolen items.
"I'm not trained from a security point of view," he said. "So I am unaware - how the gentleman or how the LPOs handle these situations and what is right and what is wrong."
The coroner issued a number of recommendations for Bunnings, including that LPOs and store managers be trained in how to deal with confrontations with customers.
He also asked the company to review LPO performance and keep records of all incidents involving them.
Bunnings told the coroner it had taken several measures following issues that arose during the inquest, including updating its code of conduct to make it clear when physical force can be used.
It has also since updated its agreement with contractors.
Bunnings operation director Ryan Baker told AAP the coroner's recommendations would be reviewed in detail.
"We're aware of the findings of the Victorian Coroners Court regarding this matter and our thoughts are with Mr Georgiou's family at this time," he said in a statement.
