Thank you. I have one more scenario....
A 4/10 @ B20....A lines up to go for it....then, they run the field goal unit onto the field (10 players), 1 player from the offense doesn't quite leave the field (stays on the field-next to the sideline). A is charged with a delay of game penalty. After backing A up 5 yards, they stay in field goal formation. The sneaky 11th player just backs up 5 yards. He is still unnoticed and on the LOS. The holder takes the snap and throws a pass to the wide open 11th player for a TD. I flagged the play for illegal participation because he never re-established himself by going inside the #'s. In my opinion this was a new play and he had to re-establish eligibility. Correct call?
Eligibility is not the issue, and the penalty for failing to be inside the numbers is IF, not IP.
Without the DOG, it's pretty clear you've got IP (compare 9.6.4B). (You can't get both: DOG is a DB foul, and it wouldn't be IP until the snap.)
After enforcing the DOG, the pretended substitution is over, and you cannot flag IP. But it's still IF when he fails to come inside the numbers.
March them back enough, and the coach might re-think his little trick play.
