A roughing-the-passer flag changed the outcome of an NFL game Sunday, and by almost any definition of the penalty, it was an awful call.

Green Bay Packers linebacker Clay Matthews delivered a clean, timely hit on Minnesota Vikings quarterback Kirk Cousins as he delivered the ball late in the fourth quarter with the Packers holding a 29-21 lead.

Matthews hit looked clean

Matthews didn’t go high, he didn’t go low, he wasn’t late, he didn’t put his weight on Cousins and he didn’t use his helmet.

No matter. The yellow flag was thrown. Instead of a Jaire Alexander interception that would have all but sealed a Packers win, the Vikings kept the ball and picked up 15 yards on the penalty. Cousins then led a game-tying drive for the final 29-29 score that would hold when neither team scored in overtime.

Clay Matthews blasts roughing call

After the game, Matthews was heated.

“I have so many emotions kind of running through as far as what a terrible call it was,” Matthews told reporters. “But at the same time, I don’t know what else to do. I don’t know. You let me know. You tell me. Did I put pressure on him? I thought I hit him within his waist to chest, I got my head across, put my hands down. And to call it at that point in the game is just unbelievable.”

Another roughing call on Matthews

It’s the second straight week Matthews has been called for roughing at a critical game juncture. While last week’s fourth-down hit on Chicago Bears quarterback Mitchell Trubisky was late and boneheaded, Sunday’s was a good football play.

“Last week, OK, shame on me,” Matthews said. “This week, that’s unbelievable. The worst part is, we’ll probably send it in, and you know what they’re going to say? They’ll find fault on me because they’re going to agree with the refs. I don’t know. It’s a difficult call to call.”

Roughing calls changing game outcomes

It’s also the second straight week a dubious roughing call changed the outcome of a game. In Week 1, Cleveland Browns defensive end Myles Garrett got flagged for roughing Pittsburgh Steelers quarterback Ben Roethlisberger on a call that the NFL admitted it got wrong after the fact. The call gave a Steelers drive new life that ended in a touchdown instead of a likely field goal in what turned out to be a 21-21 tie.

Quarterbacks are obviously the most valuable players on any football field and appear to be garnering undue protection from clean football plays as the NFL looks to protect its assets.

It leaves players like Garrett and Matthews at a loss on how to play the game.

Matthews: ‘I don’t know what to do’

“You see how it changed the game,” Matthews said. “I know there’s an emphasis on protecting quarterbacks, but it’s gotten out of control. I don’t know what else to do. It’s frustrating because Jaire’s interception — I mean that’s game, right? Instead, they go down and score, overtime, this and that.”

Matthews said he did not receive an explanation from officials on why he was flagged.

Officials give explanation

Referee Tony Corrente told ESPN that Mathews was flagged for driving Cousins into the ground, and that his use of his body weight was not considered.

“When [Matthews] hit the quarterback, he lifted him and drove him into the ground,” Corrente said. “It has nothing to do with the rule of full body weight. It has nothing to do with helmet to helmet. He picked the quarterback up and drove him into the ground.”

Whatever Corrente saw seems a mystery to almost anybody else watching the game.

Whether the NFL acknowledges a mistake as it did with Garrett, fines Matthews for complaining, or both, one thing rings true.

The Packers ended up with a tie against a division rival in a game they would have almost certainly won without that call.

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