Would you call this????

[BktBallRef]

Originally posted by sm_bbcoach
As he runs, he crosses the NZ on the field in a mad dash to get off the field to his sideline before the snap. By rule this is encrochment 5 yds and in our example give A(K) its 1/G.

By rule, it's NOT encroachment. The reference can be found in 7.1.6d. I won't post the entire play, since the ruling alone addresses this.

7.1.6d
RULING: It is not encroachment for the substitute to cross through the neutral zone. An entering substitute cannot encroach until after he has established himself as a player on his team's side of the neutral zone. If B1 is unable to get onside prior to the snap, it will be a foul for illegal substitution. This foul occurs simultaneously with the snap and if penalized would be administered from the previous spot. Similarly, it is not encroachment when a replaced player crosses the neutral zone in leaving the field. (2-30-15; 3-7-2, 6; 7-1-2; 10-4-2a)

With regards to flagging the illegal substitution, if the player realizes he shouldn't be in the game and is trying to get out, we don't flag it if he's sufficiently off the field. If I count 12 and see that the defense doesn't realize it, I'll flag it and kill it when it's obvious the ball is about to be snapped.