http://www.espn.com/nfl/story/_/id/19021659/nfl-expected-pass-rule-prohibiting-leaper-block-attempts-field-goals-extra-point-attempts
NFL owners passed a rule on Tuesday that prohibits players from leaping over linemen to try to block field goal and extra-point attempts.
Sources told ESPN's Adam Schefter that the league feels the play is too dangerous and a player could get flipped over and seriously injured while leaping over the line.
The rule change was sparked by a proposal from the Philadelphia Eagles and was backed by the NFL Players Association.