Owners Make Rules Changes 3/20/13
PHOENIX - NFL owners have approved two rule changes to enhance player safety.
The owners outlawed peel-back blocks anywhere on the field; previously, they were illegal only inside the tackle box. The penalty will be 15 yards.
Also banned is overloading a formation while attempting to block a field goal or extra point. Defensive teams can now have only six or fewer players on each side of the snapper at the line of scrimmage. Players not on the line can't push teammates on the line into blockers, either.
The alignment violation is a 5-yard penalty. The pushing penalty is 15 yards for unnecessary roughness.
The owners may not pass a rule change that would prohibit ball carriers from making contact with a defender with the crown of their helmets, outside the tackle box.