The NFL Players Association has reportedly sent a letter to NFL Commissioner Roger Goodell requesting more clarity on changes to calls involving contact between opposing players.

According to NFL.com, league sources say that in the message, NFLPA president Eric Winston requested more information regarding penalties involving the new body-weight rule as well as players lowering helmets before contact. Those two stipulations are apparently still confusing bones of contention with players, coaches, and officials, while the NFLPA believes on-field personnel hasn't been adequately changed about how those rules need to be followed.

Goodell hasn't responded, which is hardly reassuring to Packers linebacker Clay Matthews, who's repeatedly been nailed by penalties for roughing the passer, including one hit on Vikings quarterback Kirk Cousins which — by all media accounts after several instant replay examinations — was by the book. Even the NFL's Competition Committee, which initially pushed for the changes with hopes that roughing calls will decrease this season, argued that Matthews shouldn't have been penalized for the way he tackled Cousins.

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The body weight rule particularly affects defenders such as Matthews who rush the quarterback. Under the new rule, a defender cannot land on a quarterback with the majority of his body weight. That's forced defensive personnel to change their tactics by landing with most of their body weight hitting the turf instead of the pivot. Even with those adjustments, they weren't enough to negate a personal foul against Browns defensive end Myles Garrett who pummeled Steelers quarterback Brent Roethlisberger during a September game. The call resulted in a first down for the Steelers, who scored a touchdown on that drive.

Buffalo Bills safety Micah Hyde has been quite vocal about the ambiguities of the helmet rule, which the NFL states is not allowed if a lowered helmet is used to initiate a tackle. Hyde argues that the physiology surround

where the head is located on the body makes it tougher to avoid helmet contact, especially in a short-yard situation.

But the rule changes have sometimes manifested into situations didn't count on, such as injuries affecting the defense. That's what happened in September to Dolphins lineman William Hayes tried to avoid a body-weight flag when tackling Raiders quarterback Derek Carr. He succeeded in that no penalty was called, although he's currently out with a knee injury he suffered during that altercation.

"It's very frustrating because any guy who's played with me, they know what I put myself through in the offseason and every week just to get to the next game," said Hayes. "To have that stripped away from me by trying to look out for somebody else's well-being and not my own is tough."

The competition committee examined footage of 68 sacks after last Sunday's slate of games and remarked that there were fewer penalties. That said, those results have done little to ease the confusion among defenders.

"Guys are losing thousands of dollars just doing their job," lamented 49ers cornerback Richard Sherman on Twitter. "Something has to change."

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