[SAump]

There is a similar scenario where the batter takes ball 4 and is awarded 1B. The batter attempts to toss his bat back towards the dugout at the same time the catcher attempts to pick off the runner on 3B. Many claim that this is interference on part of the batter.

Think about the situation as it relates to the OP. There is a very fine line here too and the defensive coach will be out there requesting why the PU didn't call interference. The PU has to be on top of it before it becomes a "what just happened" moment.