Celtic signing Joey Barton has taken aim at Manchester United legend Gary Neville.

After his sacking by Valencia, Barton believes Neville's status as England assistant coach is being questioned by the players.

The former Manchester City midfielder told talkSPORT: "Not knocking Gary Neville, he talks great about the game, but you look at his results as a coach.

"That's the objective data.

"He's not at the level everyone thought he was. Top player, top pundit, but there's a difference when you're trying to get people at it.

"Do you think the players aren't aware of that?

"Gary Neville is chipping in, giving coaching points and the players are thinking, 'what do you know?'. If he's challenging a player, they're thinking 'what do you know?'."