Blatant and avoidable. What is meant by blatant? Does it imply intent? Wouldn't whether or not it was avoidable be a judgement call?

Rynodawg,

Just some advice for the future.

Welcome to umpiring. I'm not going to get into what has already been correctly explained about the interference. However, as a new official I would suggest that during your pre-game conference with the coaches, ask, What rule book are we using today?

When you do games utilizing all three major rulebooks, (OBR,NCAA,NFHS,) it helps to start off on the right track.
They may also tell you what modified rules apply to their league. A lot of coaches assume that because your are there to officiate their game, that you have automatically, (usually by osmosis I think) know all of the rules for "their league."

Although you should, it just doesn't always happen that way.