<P> In both American and Canadian professional football , every player on the defensive team is considered eligible . The offensive team must have at least seven players lined up on the line of scrimmage . Of the players on the line of scrimmage , only the two players on the ends of the line of scrimmage are eligible receivers . The remaining players are in the backfield ( four in American football , five in Canadian football ) , including the quarterback . These backfield players are also eligible receivers . In the National Football League , a quarterback who takes his stance behind center as a T - formation quarterback is not eligible unless , before the ball is snapped , he legally moves to a position at least one yard behind the line of scrimmage or on the end of the line , and is stationary in that position for at least one second before the snap , but is nonetheless not counted toward the seven men required on the line of scrimmage . </P>
how many players on the line of scrimmage in american football
at least seven players