A product of the former Heath Hayes Youth team, Wallis has matured over the seasons and now has an excellent all-round game. Karl made the most appearances during the 2007/08 season. Playing wide on the left, Wallis is an attacking winger with natural goal-scoring ability.

The fastest postman in Cannock, Wallis uses his job as a form of training, practicing his delivery skills everyday. Sadly, on the pitch Wallis has to deliver a ball not an envelope, which may explain the lack of crosses from the left.