 Any offensive lineman not covered up by the fourth man on the line of scrimmage is an eligible receiver if he is wearing an eligible receiver number (1-49, 80-89).Defensive Linemen – There must be three defensive linemen, and they must line up on the nose, or can line up inside foot-to-outside foot outside of an offensive lineman Linemen must rush inside if nose up or slanted into if shaded, and they must make contact before any movement to the outside is made.Blitzing – Only one non-lineman can blitz at a time.