After the ball is dead, Team A sends a player off the field. After the ready for play whistle, they send on 4 players and 5 leave the huddle. One of those players who left the huddle stops short of the sideline and assumes a wide out position. The ball is then snapped.

Rule 9-2-2-b states "No simulated replacements or substitutes may be used to confuse opponent's. No tactic associated with substitutes or the substitution process may be used to confuse opponents."

Discussion:
In my eyes this is a foul (live ball) regardless whether the defense recognizes and covers the player near the sideline. However, I've talked to several experienced officials who say that this tactic may not be illegal if the defense covers the player and the offense doesn't gain an advantage. In other words, if the defense covers him, they aren't confused - no foul.

I think it is illegal either way but I thinl vetern officials would proably let it go if the defense regonized it, but before the next play the official would proably tell the coach or team captain that that is illegal and next time they will throw a flag

I'm in agreement with Smoke and would make it a very stern warning to the head coach that he is violating 9-6-4-c. If the defense reacted to this late, I still would flag it. This is the type of nonsense the NFHS and NCAA is trying to end.

9.6.4B. Play: Following a kickoff return, A1 and A2 enter the field while A3, A4 and A5 move toward the sideline. A5 stops within 15 yards of the ball while A3 and A4 continue to the team box. The ball is snapped without a huddle and the quarterback throws a forward pass to A5, who has gone downfield as a wide receiver. Ruling: This play is illegal as a pretended substitution is used to deceive the opponents. The penalty of 15 yards for the illegal participation foul will be administered from the previous spot as the foul occurred at the snap. (9-6-4c)

I agree with Smoke and Tom that if the defense recognizes the deception, a warning to the coach would be sifficent.

How about a slightly different factual scenario, where there is no substitute or replaced player used. Team A runs one play and after the play they are loosely grouped near the ball. The R blows the ready for play and A1 leaves toward the sideline while the rest of Team A huddles. They break the huddle, meanwhile A1 has stopped at the sideline. A1 goes downfield at the snap, unobserved by Team B, and catches a touchdown pass.

An NCAA team I'm familar does something very close to this
and we feel that this is not using the substitution process
and therefore is legal even if team B fails to reacts.

They in fact did this twice in the game. The defense covered
the player on the first attempt. Team A calls TO to change play.
The second time, team B did not cover and the play ended with a Team A score.

I think you must read intent. This situation may be only a coincidence that the player is moving to his position along with the substitutes. Do EVERYTHING you can to avoid throwing a flag such as verbally telling the end if he is on the line (or not) so that the defense can clearly hear you and be aware of the player. Then after the play is over, warn the coach of possible deception. This is a 15 yard penalty and would be a terrible call if the intent was read incorrectly.

In reply to Shief's post. This play was premeditated. The coach sprung this on us during the pregame conference.

In reply to jwilde1665. Under NCAA rules, this is not a foul if all team A players who participated in the previous play were inside the 9 yard marks after the ball became dead and before the next snap. Incoming substitutes have to be inside the 9 yard marks after the ready and before the snap.

I believe it would be the same ruling for NFHS. There is the same requirement to be within a certain distance from the ball after the ready for play.