Shelvey chose Colback in his dream XI from players he played with throughout his career for In The Box.
He explained, "There was a reason that it happened which I can't really go into because it was probably to do with Rafa (Benitez) and Rafa sort of killed him to be honest with you but he's one of them where he comes in and trains with us now.
"He's still got a contract at Newcastle and he comes in and trains and he's probably near enough the best trainer. Knowing that you're not going to play is so hard.
"When he went to Forest, his missus and kids moved to Forest so he gets a train to Newcastle every morning from Nottingham and that's dedication because he could just sack it off and say, 'No, I'm not doing that' and I don't think the club are that bothered about him turning up for training.
"He still comes in and puts it in every day and I think hats off to him. But as a player and what he used to do? Obviously, win the ball and just give me a five-yard pass next to me so I can go and do my stuff. That was a big thing in the Champ and why we succeeded in the Champ."