NRL great Ian Roberts claims that he has irreversible brain damage due to repeated head injuries during his rugby league career.
The 52-year-old is among 25 former NRL players who last year took part in a study into concussions and the effects on the brain.
Roberts played 12 seasons in the NRL for the Rabbitohs, Sea Eagles and Cowboys along with higher honours in State of Origin and the Kangaroos. He revealed to the BBC that he was knocked unconscious at least 14 times during his career.
"I've had some complications with my mental health since retiring from rugby league," he told the BBC.
"My first major concussion was in my early teens, and when I turned professional I was knocked unconscious on 14 separate occasions."
Roberts, who was the first NRL player to come out as gay in 1995, went into acting after retiring in 1998 and told the BBC that he struggles to learn his lines.
"In the last five years I've noticed my recollection of things has slowed down and my memory isn't as sharp as it was. I first realised it at rehearsals for plays because my ability to learn lines has deteriorated. I'm just not as sharp as I was in the past."
"I was fully aware there was something wrong with me, but to be told I had scarring on the brain was surprising. It's irreversible damage."
The study, performed by neuroscientist Dr Alan Pearce and Melbourne's La Trobe University last year, involved 25 former rugby league players who were asked to perform five tasks relating to memory, short-term learning and attention, reaction time and fine motor skills.
The results were compared with men of similar ages who did not play professional sport.
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