Coach wants his TO, then give it to him. Then, assess the T that goes with it. It may be okay to "not quite hear" the request the fist time, but if he continues, give it to him. It's not your fault that the assistant (or his book) didn't bother to help the head coach!
You could have said something like, "Coach, team B already had the ball at their disposal to throw it in. Therefore, I couldn't grant you the TO, and besides, you don't have any left."
Then listen to him THANK YOU profusely for missing the call!!
