The NFL owners voted on four rules changes during their annual meetings, all of which will be implemented for the 2013 season.
Most recognizable among them is the so-called "Tuck Rule," which no longer will exist. But all of the owners' rule book adjustments could lead to significant moments throughout coming NFL games.
• The crown-of-the-helmet rule
In the ongoing battle by the NFL to limit head injuries for its players, the league's owners voted in a rule that will penalize a player 15 yards for initiating contact on another with the crown of his helmet. The rule only pertains to tackle attempts made outside the tackle box and "incidental contact" will not draw a flag.
So ... good luck with that, NFL officials. I know it's easy to rail on officials for mistakes, but the amount of split-second judgment calls they're asked to make continues to rise. This one figures to be even harder to determine than the defenseless-receiver rule, which led to an endless stream of questionable flags last season.
Not only will officials have to make sure a player was out of the tackle box for this rule, but also they'll have to decipher intent. What if a running back stumbles and drives his head into a defender? What if he's covering up the football to protect against a fumble and happens to bring his head down? Those should fall under the incidental contact allowance, but picking and choosing during a game will be brutally difficult.
• The peel-back block rule (aka, "The Brian Cushing Rule")
As it did with "The Tom Brady Rule" a few years back, which prevents defenders from diving low at a QB in the pocket, the NFL has again reacted to a serious injury inflicted on one of its star players. This time around, it's Brian Cushing, who suffered a season-ending knee injury on a peel-back block.
That type of play -- in which a player blocks an opponent below the waist after approaching from the side or behind -- no longer can occur; before now, they had been outlawed inside the tackle box.
• The tuck rule
It's about time. Maybe we can call this "The Other Tom Brady Rule" -- of course, it was Brady and the Patriots who benefited from this call during a 2001 playoff game.
Brady's infamous play against the Raiders, in which Brady lost the ball as he pump-faked and then brought it back to his body, would now be ruled a fumble. Previously, it would have stood as an incompletion.
This has long been one of the league's most confusing and hardest to judge rules.
• The unnecessary-challenge rule
This one burned Jim Schwartz on Thanksgiving Day when he threw the challenge flag on a Texans touchdown run -- all scoring plays are reviewed, thus Schwartz's challenge was extraneous.