tim cahill
Player Valuation: £50m
In the respect that he saw out his contract he was, but he did string the club and fans along by stalling on a new contract. He always seemed to be on the lookout for a new job if something half decent cropped up, so he's not someone I'd class as loyal even before his actions after he left.
He was only showing ambition. I thought you valued that more highly than loyalty?!