Dual rugby international Sam Burgess called his ex-club coach Mike Ford a "snake" and accused him of "sabotage" as he opened up about England's disastrous 2015 World Cup.
Burgess, who made a high-profile switch from rugby league to union just months before the tournament, claimed Ford used him as a pawn in a bid to become England coach.
Burgess retired last year after a glittering rugby league career, but the ill-fated World Cup campaign stands out as a low point in his career.
He said he confronted then Bath coach Ford after the World Cup, when Stuart Lancaster's England - the tournament hosts - crashed out at the pool stage.
"I came back from the World Cup and I literally went in his office and said, 'Hey Mike, I don't trust you. I think you're playing games behind my back,'" Burgess told the House of Rugby podcast.
"'You used me as a bit of a pawn in your game of chess. I can't put my boots on and play for you every week.'"
Burgess said Ford used his son - England flyhalf George - to "infiltrate" the team camp. He also said the elder Ford had stirred up stories in the media to unsettle him.
"I just think people behind the scenes were playing a deeper game," he said.
"Mike Ford wanted the England coaching job, so his job was to try and sabotage Lancaster, and his decision-making and his coaching methods."
He added: "I'll never forget Mike's face when I said to him, 'Mike I don't respect you any more, I really don't. I think you're a bit of a snake.'
"And I'll never forget the little quiver that I got from him."