forward pass

In football's early days, forward passing was illegal, and it still is in football's predecessor sport of rugby. As the game evolved in the first half of the 20th century, the forward pass was legalized with certain restrictions.

• Only an offensive player may throw a forward pass, and it is only legal on a play from scrimmage (not on returns or any other sort of play).
• There may be only one forward pass per play; any other throws must be laterals.
• The ball must be thrown from behind the line of scrimmage. The passer is usually the quarterback, but any eligible receiver is also allowed to throw the ball. (The five offensive linemen are considered ineligible: the center, guards and tackles.)
• A forward pass must be obviously intended for a certain eligible receiver; if the ball is not so intended, and the pass falls incomplete, the offensive team may be penalized for intentional grounding.