A senior official I know told this story once. A1 had just committed his fifth foul. The coach, timer and player had all been notified. The coach, however, did not go to the bench, choosing to stand and look at the ref. After a few seconds, the he asked the coach, "Coach, do you have a sub?"
The coach answer angrily, "I have 30 seconds!"
The ref simply said, "Don't take 31."