A masters games shot putter thought a competitor was outside the safety lines before he heaved the shot which hit him in the head and claimed his life.
A coroner's inquest has opened into the death of Bruce Clark, who died in hospital 10 days after being felled at Mt Smart Stadium during last November's North Island masters track and field championships.
Mr Clarke, 77, was believed to have been retrieving his shot put during the practice rounds when he was hit.
Peter Crawford, who threw the fatal shot, told the coroner's court in Hamilton on Monday that he saw Mr Clarke walking away from him outside the white safety lines as he was preparing to throw.
Mr Crawford then stood in the circle with his back to the course and signalled he was about to throw.
He then turned and threw in one motion before realising Mr Clarke was in danger. He tried to warn him by shouting at the Hamilton man to get out of the way.
The projectile hit Mr Clarke on the right side of the head.
When asked if it would have helped to have had more safety instructions before the competition started, Mr Crawford agreed.
"Yes it would have but there's also an element of common sense that between the two white lines is an unsafe area which every thrower is conscious of," he said.
Under cross-examination the deceased's daughter-in-law Vanessa Clarke asked him to explain why he took the risk when her father could have been unaware he was about to throw.
"I thought Bruce was safe as he was outside the lines," Mr Crawford said.
Event co-ordinator Murray Free admitted the practice run should not have gone ahead due to a lack of available supervision officials.
"There has been a huge increase around safety protocols since Bruce's death which has been a big wake-up call for everybody to sharpen up their act," he said.