Rule 6.06c "He interferes with the catchers fielding or throwing by stepping out of the batters box or making any other movement that hinders the catchers play at home base."
So by "making any other movement" includes his normal swing? It was McCann stepping up and into the backswing. Sounds like it was ump interpretation.
Oh well.
The rule includes long swings but states that it's a judgment call for the umpire. The umpire made a judgment call there and I had no issue with it.
