Free blocking zone.

Question
QUESTION: I'm couching a football team in Mexico. The boys are 15-16 and 17-18 years old. We are running the doublewing formation, we are the only one running this offense in the conference.
When the other team can't stop my pulling guards, their defensive ends and cornerbacks start block below waist my fullback and guards, sometimes they use the helmet because don't have the time to move it to one side so they spears our players knees.
The officials say:"The rules don't say anything about blocking below waist by the defensive team". I think they are wrong and they missed something in the translation of the rules.
I just found something relative in the rules book: Approved Ruling 9-1-2 section XVII (about spearing).
If I'm right, is it possible get a letter form an expert like you where you explain that rules protect both teams, offense and defense, especially blocking below waist out of the free blocking zone?

ANSWER: What level are we speaking of?

---------- FOLLOW-UP ----------

QUESTION: Let's talk just about the 17 and 18 years old boys, I think is high school level (2 and 1 year before college). Anyway, our conference plays under NCAA rules. I hope you can help me. Thank you.

Answer
NFHS Rule 2-3-7...Blocking below the waist is making initial contact below the waist from the front or side against an opponent other then the runner.  Blocking below the waist applies only when the opponent has one or both feet on the ground.

Per Rule 2-17-1 the free blocking zone allows blocking below the waist as long as the offensive & defensive players are both on the line at the snap & in the zone.  The zone is 4 yards either side of the snap & 3 yards behind each line of scrimmage.

Therefore, it is probably legal from the defensive end, never from the cornerback since the CB would not be on the line of scrimmage at the snap....

If this totally confuses you please feel free to call me @ 423.605.3035 (eastern time) & I can probably explain it easier on the phone...

Andy....

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