NFL's memo warns defenders about punch-out plays, using Jack Campbell as an example

The Lions aren't happy with the NFL's officiating office.

Head coach Dan Campbell said after last week's game that the league office made the call to throw a flag on the Lions' fourth-down trick play that negated a touchdown. If that truly was the case, it was the right call, but the wrong procedure.

Then, the league suspended defensive back Brian Branch for a game after his postgame fight with JuJu Smith-Schuster.

Now, according to Lions defensive coordinator Kelvin Sheppard, the league has sent out the "Jack Campbell memo."

The league, according to Sheppard, used the Lions linebacker as the example of aggressively - too aggressively in the league's view - trying to punch out the ball.

Look at Jack. I mean, they just sent out a memo and the tape," Sheppard said, via Kory Woods of mlive.com. "I mean, the way Jack is doing it, it's violent; it's aggressive; and it's the way we play. We won't make excuses, and I hope it continues to show up and uptick as we progress in the season."

Sheppard added that the memo emphasized ensuring defenders are punching the ball and not the opposition.

Whatever that means," Sheppard said.

The memo, as Lions reporters have noted, used video of Campbell and not of 49ers defensive lineman Alfred Collins, who punched Kyren Williams in the helmet, turning his head, before punching out the ball on the 1-yard line. The 49ers recovered the fumble and won the game.

Campbell is fifth in the NFL with two forced fumbles and has a fumble recovery. Lions defensive lineman Aidan Hutchinson is tied with Bills defender Joey Bosa in forced fumbles with four.