Ball!ball!ball!

[jdw3018]

Regardless of whether it's a violation or not (it's not according to the Rules, but if your state wants it enforced that way then you should do so), the real question here is the coach saying it hasn't been enforced before.

IMO, this is no different than telling a player she can't wear illegal headwear, or an illegal brace on her hand, or any other "administrative" enforcement. You will almost always hear "nobody else has made me do that."

The only response you can give is that you have been directed to enforce that rule and that in your games it is going to be enforced.