If Soccerbase is to be believed, he only started refereeing league football towards the end of last season. This may be a load of nonsense, but I'll admit I'd never heard of him before I came to do this piece. He may share his name with a former Saint, but he's never taken charge of one of our games before. As a result, this will be an extremely short article!
In 15 games this season, Mr Muir has issued four red cards. It's an average of neary one every three games and, as he hasn't sent anyone of for a while, there's a fair chance of a red being shown on Saturday. One of the players he has sent off is Motherwell's Paul Quinn when the Steelmen lost 1-0 at Kilmarnock earlier this season.
Not a lot else to be said - his card count seems to vary so it's anyone's guess what will happen this weekend!