Manase Fainu says he helped prevent fellow inmates from attacking Jarryd Hayne when Hayne arrived at a Sydney prison.
"We looked after him at Windsor," Fainu said.
"We found out a day before that he was coming into the jail.
There were talks already, the Aussie boys were saying, 'When he comes in, we're going to blade him 1-2-3'.
So there were boys already planning it up."
Fainu said some inmates wanted to support Hayne because he was an Islander and was still contesting his charges.
"He's an islander, and islanders stick together in jail.
So two other boys … said 'We're going to back him, he's an islander. He's still fighting his charges... When he comes in, we'll sit him down and ask if he did it or not'.
The pair crossed paths at Geoffrey Pearce Correctional Centre in Berkshire Park.
Fainu, 28, was released on parole on Friday after spending more than four years in prison for stabbing a man during a brawl outside a Mormon church dance in 2019.
The former Manly hooker last played in the NRL in 2019.