At the instant the ball is put in play, at least seven players of Team A must be Line Players (as defined in Rule 4, Section 1, Article 2). Conversely, Team A can never have more than five players in backfield positions.
On all scrimmage plays at least five Line Players, including the Centre, shall be identified as ineligible pass receivers and must be positioned in a continuous, unbroken line. On scrimmage plays in which Team A punts the ball, the continuous unbroken line of ineligibles must include two ineligible Line Players on each side of the Centre (aka the Long Snapper). In addition, one player at each end of the line shall be identified as an eligible pass receiver.
Any other Team A player is an eligible pass receiver, if so identified by playing number and, at the snap of the ball, is not a Line Player and is clearly occupying a backfield position.
Eligible receivers will wear numbers from 0-49 and 70-00.
Ineligible receivers will wear numbers from 50-69.
At any time during the game, an eligibly numbered player may be added to the list by entering the field of play and reporting to the Referee.
If an eligibly numbered player who is not on the list participates at an ineligible receiver position (as a Line Player from tackle to tackle), his team will be warned once and his number will be added to the list. If this occurs a second time, a Procedure penalty shall be called.
A maximum of 2 players wearing an ineligible number (50 — 69) will be allowed to line up in an eligible position as an end or in the backfield after reporting to the Referee prior to a scrimmage play. The player must report to the Referee before EACH play that he wishes to play in an eligible position. The referee will inform the opposing team and all officials of the player number and position he will be playing.
Team A Line Players after having assumed a three-point or four-point stance may not break their stance by lifting a hand, however they may point, signal, shift or move slightly in a manner that does not draw the defense offside. All Team A Line Players, including the Centre, must become stationary and remain motionless for at least one second prior to the snap of the ball.
The Centre is allowed to bob their head any number of times prior to the snap of the ball provided that the Centre pauses for one second between each head bob and remains completely motionless for at least one second immediately prior to the ball being snapped.
No player of Team A, who is a Line Player, shall be moving towards the opponent's Goal Line when the ball is put in play.
EXCEPTIONS: Rule 6, Section 4, Article 4, Note 4
Prior to the game, a team is required to designate three players who shall be permitted to alternate for each other during the game at the Quarterback position exclusively. Not more than one such player may be in the game at any time and none of the three can enter the game as a member of Team B.
NOTE: For the purposes of this Article 5, the duties of the Quarterback position may include punting, place kicking and kicking off. If a team designates three Quarterbacks for a game, the player designated as the third Quarterback shall not be eligible for kicking duties.
If a team is using its full complement of international players, it shall, prior to the game, designate four international players as special teams players, who shall be permitted to enter the game at another position, only on the understanding that another international player on that side of the ball is required to leave the game for that play. Such player may enter the game on an unrestricted basis, only if another international player is removed for the balance of the game.
If a designated international participates in the game illegally: