The NFL says Williams touchdown run shouldn't have counted. (US Presswire)

There was a controversial play in the Redskins-Panthers game on Sunday that resulted in a very rare DeAngelo Williams touchdown run, when the Panthers back scampered 30 yards to the end zone.

A referee blew an inadvertent whistle during Williams run, and the play was called back. But after conferencing, the referees awarded Williams the touchdown. According to the NFL, the corrected ruling was wrong and the Panthers should not have been given a touchdown.

"In Sunday’s game between the Carolina Panthers and Washington Redskins, the Panthers were incorrectly awarded a touchdown following an inadvertent whistle," an NFL spokeperson said in a statement.

Rule 7, Section 2, Article 1 (n) (i) of the NFL Rule Book (page 32) states that when an inadvertent whistle is blown while the ball is in play, "the ball becomes dead immediately" and "if the ball is in player possession, the team in possession may elect to put the ball in play where it has been declared dead or to replay the down."

Per the rulebook, Carolina should've been given the choice of a first down at Washington's 17-yard line or replaying first down from Washington's 30.

The issue in this instance arose because all touchdowns are now reviewed automatically. The officials confirmed Williams did not step out of bounds and ruled that the play resulted in a touchdown, despite the whistle being blown.

However, Rule 15, Section 9 of the NFL Rule Book (page 90) states that an inadvertent whistle is one of eight non-reviewable plays.

Therefore, the non-reviewable nature of an inadvertent whistle overrules the automatic reviewable nature of a scoring play.

Williams' decent game was inspired by the Redskins deciding that their matchup against the Panthers on Sunday was their "homecoming." And he joked about the king and queen blowing the whistle on him.

If the referees had gotten the ruling on the field correctly, it might not have been quite so funny. But that leads to a bigger problem -- an inadvertent whistle could have kept Williams from scoring on a play where he clearly didn't step out of bounds. It wasn't even close.

Of course, the bigger problem is that Washington's Perry Riley would've probably been able to push Williams out of bounds before he got into the end zone. Along with Riley, multiple Redskins stopped when the whistle sounded, as they're trained to do.

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