The midfielder is in the form of his life and was again on the scoresheet in victory at Everton yesterday.
McClaren stated: "When I was at Derby we took him on loan and he had just had an injury.
"He came to us to get his fitness back and games. You could see the potential and wow he is fulfilling that now and he is different. He is unique. He is forward-running with and without the ball.
“He is such a threat and he is probably a quicker runner with the ball than without the ball. He beats players, can score, is composed and can assist."