ARLINGTON, Texas – There's a new taboo in the NFL: hitting too hard.

Late in the Philadelphia Eagles' 33-10 rout of the Cowboys, Dallas kick returner Dwayne Harris decked the Eagles' Nolan Carroll as a punt hit the turf inside the Dallas 10-yard line. A scuffle ensued.

Harris was flagged for unnecessary roughness, and Cowboys head coach Jason Garrett got a curious explanation: "They told us that he hit him too hard unnecessarily."

Dwayne Harris (R) and Nolan Carroll exchanged words after a punt. (AP) More

The hit appeared legal. It was not to the head, and it was not from behind. Carroll saw Harris coming. There was no fair catch on the play, either.

"If Dwayne were catching the ball," Garrett told reporters after the game, "not in a fair catch situation, that guy would've probably hit him in a very similar fashion. So my understanding is as long as you don't hit him in the head, you're allowed to do that."

Garrett said he plans to send the play to the league for review.

Harris, speaking at his locker after the game, was just as mystified.

"My job is not to let the guy catch the ball inside the 10," he explained. "I've been doing it all season."

Asked why he was flagged, Harris gave the same reasoning Garrett got.

"They told him I hit him too hard," he said.

Harris shrugged, saying he had never heard of hitting too hard as a crime in football.

Garrett echoed it in his news conference: "I don't think I've ever heard that one."