"If you are looking at a top-quality centre-half, and the attributes you need, then Matthew has got them in abundance," Cunningham told the Press Association.
"He just needs games under his belt now. He just needs a consecutive run of games which he has not had for the last couple of seasons.
"He's a great athlete. He's quick over the ground. He reads situations, has a wonderful left foot, and good composure.
"I think he is the signing of the season. When you consider we got him for a cut-price deal, it's an outstanding piece of business.
"If he keeps progressing the way he is, then he'll be knocking on the England door sooner rather than later."
