Rangers defeat to Celtic in the Scottish Cup final was as frustrating as it was disappointing for a number of reasons. Refereeing decisions, wasted opportunities in the final third and the one player who Philippe Clement can really trust costing his side a goal in Jack Butland – what could go wrong, did go wrong, despite a solid tactical plan. The game plan was a success primarily because of who the manager picked to get the job done with one Rangers player in particular doing enough against Celtic to justify his selection. READ MORE: Rangers biggest ever wins including three 13-0 annihilation…