Clark: Newcastle's Barton a top four player
"I saw then what a top player he was and nothing has changed my view of him. Don't forget I have also seen him at the training ground before I left for Norwich and he really is what I call a driven player.
"He wants to impress, and Joey Barton is the type of player United are going to need if they are going to get back into the top four.
"He is good enough to play in a top-four team. That's how good I think he is.
"He is a fantastic signing for my old club, and if it has not happened for him yet there is no doubt in my mind United fans will soon be seeing a lot more from him."