[NFump]

Tim,

I don't enforce this at the local league level, however, I do mention to them when they come out that they're supposed to have a mask on. This usually gets them to start sending out one of their bench players to warm up the pitcher(yes, he has a mask on). At District and State levels(and beyond as well), it's enforced. Usually the response is the typical that's crap, first time I've ever had it enforced or heard of it but never any "heated" arguments.