Josina Anderson explains why Vontaze Burfict plans to challenge his five-game suspension with the full backing of the NFLPA and the Bengals. (1:06)

In March, the NFL amended its rule book in a way that often goes unnoticed by the majority of fans and media. It added a new qualification for defenseless player protection, part of the league's larger effort to minimize the chances for injury-producing contact.

Rule 12, Section 2, Article 7(a-2) grants protection to "a receiver running a pass route when the defender approaches from the side or behind." In other words, defenders would be limited in the ways they could disrupt route running on a pass play.

At about the same time, NFL owners enhanced their discipline policy to encourage officials to eject, or the league office to suspend, players for particularly violent or flagrant hits to the head or neck area -- even on a first offense. The new emphasis was a clear warning that the league planned to further intensify its focus on the issue for the 2017 season.

Vontaze Burfict was not penalized during the game for his hit on the Chiefs' Anthony Sherman. Photo by Lee Coleman/Icon Sportswire

And then, in the second week of the preseason, along came one of the NFL's most notorious and dirtiest players. Cincinnati Bengals linebacker Vontaze Burfict laid out Kansas City Chiefs fullback Anthony Sherman as he ran a pass route with a hit that caused Sherman's head to snap back before he landed on his back. Sunday night, ESPN's Adam Schefter reported that the NFL had suspended Burfict five games for the hit, pending an appeal.

Referee Walt Coleman's crew did not penalize Burfict for the hit, but the league office reviews every play of every game, even in the preseason, for potential fines and other discipline. Although there has been no formal announcement, the defenseless player protection rule -- and the new emphasis on ejections and suspensions for dangerous hits -- each appear to be part of the explanation.

But the existence of the rule, and the heightened emphasis against flagrant hits, does not fully explicate this outcome. Neither does Burfict's history, which elevated what might have been a one-game suspension for a first offense into five games. It's fair to ask whether Burfict's hit, while forceful and violent, was illegal at all.

As I noted Sunday night, the NFL rule book spells out three types of contact that are illegal against a defenseless player:

"Forcibly hitting the defenseless player's head or neck area with the helmet, facemask, forearm, or shoulder." "Lowering the head and making forcible contact with the crown or 'hairline' parts of the helmet against any part of the defenseless player’s body." "Illegally launching into a defenseless opponent. It is an illegal launch if a player (i) leaves both feet prior to contact to spring forward and upward into his opponent, and (ii) uses any part of his helmet to initiate forcible contact against any part of his opponent’s body."

When you watch the video above, you see Burfict lead with his right shoulder after he approaches from Sherman's left side. It's possible, but not at all certain -- at least from the available angle -- that he made forcible contact with Sherman's head or neck area. In a statement defending Burfict, the Bengals called the contact "shoulder to chest," which would be legal.

Burfict did not lower his head or make contact with any part of his own helmet, eliminating the second possibility. Did he illegally launch himself toward Sherman? The video does show both of Burfict's feet leaving the ground, but again, there's no apparent contact with his own helmet.

The Bengals, in fact, disputed whether Sherman merited defenseless protection at all. In an apparent reference to the requirement that a defender approach "from the side or behind," the Bengals said Burfict "engaged his opponent from the front."

UPDATE: Independent of the defenseless player rule, the NFL prohibits "unnecessarily running, diving into, cutting, or throwing the body against or on a player who (1) is out of the play or (2) should not have reasonably anticipated such contact by an opponent, before or after the ball is dead." It is considered unnecessary roughness, and could qualify as a penalty in this instance. But it does not require defenseless player protection and, frankly, it would be preposterous to think that it alone could lead to a five-game suspension even for a multiple offender.

So, in the dark of the night, we have suddenly plummeted into a classic NFL story of a player removed from the field for debatable reasons. Coleman and his crew were forced to make a split-second decision and can be excused for failing to flag a hit that took place away from the ball. But the league office has the advantage of controlled and timeless video analysis. We can only hope it has seen, in a definitive manner, more than what we have just discussed.

Burfict's reputation is both well known and well deserved. But this suspension would eliminate a third of his season. Even if the league has chosen to make an example of him, the evidence must be clear. At this moment, at least, it is not.