Ex-Celtic star Roy Keane has been branded a "bully" by Jon Walters as their long-running feud was reignited.

The pair were embroiled in a heated argument during Ireland training back when Keane was Martin O'Neill's assistant.

Then-Burnley striker Walters was nursing a knee issue but was slaughtered by Keane for refusing to train, leading to the pair squaring-up and having to be separated.

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It had been reported that the pair were also at loggerheads when at Ipswich Town previously.

During a chat with Off The Ball Roadshow, Keane went off on Walters, blasting him for having a big mouth and doing television interviews despite "not kicking a ball" in two years.

The former Manchester United captain also criticised the retired forward for crying on TV while opening up about the death of his mother and brother.

Keane said: "Jon Walters talks a good game, imagine if he had a good CV.

"Imagine if he won a trophy.

"When players are turning up and creating stuff. Do me a favour.

"He's a bluffer.

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"He goes on TV, how harshly he's been treated by me.

"The crying on TV.

"He's not kicked the ball for Burnley for two years. Lay low for a while, take it easy."

Walters, 35, responded on Liquid Football's podcast, claiming Keane's comments were a mark of what he's really like.

And he revealed that Keane never scared him on or off the pitch - which is why the Irishman may hold a grudge against him.

He said: "The football side of it I can take, the medals and all that doesn't bother me.

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"I stood up to him more than once and that might get to him, I don't know.

"The other stuff is a bit close to the bone.

"He was an unbelievable player and known as a hard man on the pitch.

"But just because someone has a sharp tongue or a stare doesn't make them a tough guy.

"I was never scared as a player, when you have bullies try and bully you I always try and stick up to it.

"The crying on TV stuff was something I never expected.

"It shows a side of him that I know."