Mike Pettine joked that he learned from the master when he was given the nickname “Blunt Force Trauma.”

Pettine referred to his father, legendary high school coach Mike Pettine Sr. at Central Bucks West outside of Philadelphia. As he heads into his first game as an NFL head coach, Pettine takes advice from his father, whether he wants it or not.

“He sends me some emails that are pretty entertaining as he’s watching the film,” the Browns coach said.

"Entertaining: is relative.

“The stuff that he sends, sometimes how it’s written it annoys you a little bit, but he’s right,” Pettine said. “Most of the time, he’s right. I don’t want to tell him he’s right all the time, but most of the time he’s right.”

The emails actually go to the entire defensive staff, not just the head coach.

“I get two or three a day,” defensive coordinator Jim O’Neil said.

With no shortage of information or demands.

“He’ll tell you every play you need to rep for all three days in practice -- give you the play numbers,” O’Neil said. “The iPad was the worst thing ever invented because he’s watching the game before you’re even home. You’ll get an email Sunday night about what you should have done in this situation or who screwed it up.

“It’s actually grown to the whole defensive staff gets them now, so everybody gets the Mike Pettine Sr. emails. The worst thing you can do is respond.”

O’Neil was only partially joking. In April, Pettine Sr. sent a 40-page document to give to offensive coordinator Kyle Shanahan. This week the communiques have flown fast and furious.

Pettine Jr., O’Neil and linebackers coach Chuck Driesbach all played for Pettine Sr. in high school. So they’re used to hearing from the father.

“It’s a great resource for us to have, and it’s a competitive advantage because he’s not scared to speak his mind,” O’Neil said. “He sees it sometimes from a different perspective because he’s not with us every day.

“Ninety percent of his emails are right on and you listen to him. The other 10 percent go in one ear and out the other ear because of how he says it.”