In the wake of Rob Gronkowski's season-ending knee injury, a new discussion about big hits and the NFL has emerged: Are any of the league's new tackling rules actually effective? Browns safety T.J. Ward old reporters after the game that he went low at Gronk because he knew any high hits could result in a penalty and a fine. He purposely tried to deliver the "safer" hit—the one away from the head—and still ended up delivering a concussion, along with a torn ACL and MCL. It's a double-edged sword for the NFL—if they cut out those dangerous shots to the head, they put the legs and those oh so valuable ACLs at risk. Really, the NFL is an inherently violent and dangerous game, and unless they constrain spears to only above the knees and below the shoulders (like a strike zone in baseball), bad injuries will keep flying in. 

That being said, it feels right to look back at some of the hardest hits of this 2013 NFL season so far, and determine whether or not they were actually legal. As players like Bernard PollardTroy Polamalu, and Pat McAfee have shown this season, it's actually possible for defenders to come across and deal bone-crushing hits in a legal way. Notice what's legal and what's not in The Most Brutal Hits of the 2013 NFL Season Thus Far.