*Joe Greene: A Football Life*– Friday at 9:00 PM ET

As a Pro Football Hall of Fame defensive tackle, four-time Super Bowl champion, 10-time Pro Bowler and two-time Defensive Player of the Year,Joe Greene **earned the nickname "Mean Joe" and established himself as one of the most-feared defenders in NFL history. Yet off the field, the husband, father of three and grandfather of seven goes by the name of "Papa Joe" and bears little resemblance to the 13-year NFL veteran.

The fourth season of the three-time Emmy-nominated series A Football Life kicks off Friday, September 12 at 9:00 PM ET on NFL Network with a profile of "Mean Joe" Greene. The one-hour, NFL Films-produced documentary features sit down interviews with Greene and those who know him well, including former Hall of Fame teammates Franco Harris, Lynn Swannand Jack Ham, Steelers Chairman Dan Rooney, and more.

Some of the featured quotes include:

• "When you think of me as a football player, I would like for people to think that I put it on the line every time. Good or bad, win or lose, I put it on the line." – Joe Greene

• "I just remember walking out on the deck of this aircraft carrier, and there were airplanes and there was Joe Greene. And they were both impressive. It was just sort of a presence that was there and still is today." – Jon Kolb

• "There is nobody else out there that I would put ahead of Joe Greene. By far the best Steeler of all time." – Jack Ham

• "He was special. He did signify this team. He meant everything; the way he performed, the way he carried himself on and off the field. He was it. He was the guy." – Dan Rooney

• "Joe stands as the beginning of reform and change for a football team and for a city. When Joe came, the Steelers were bad, they didn't look like they were going to get better, but Joe had the blue-collar work ethic." – Lynn Swann

• "I was depressed. I was just depressed. I did not want to be a Pittsburgh Steeler because I knew of the record." – Joe Greene on being drafted by the Pittsburgh Steelers

• "When I look back and I think about it, it was being disruptive and belligerent. I don't know how many other teams would have tolerated my antics." – Joe Greene

• "I was quitting…As I was taking those steps I was saying, 'Somebody please stop me.' Lionel Taylor, our receivers coach, said, 'Hold up a minute,' and he sat down in the car and we talked. I don't know what we talked about but I was glad we talked because I went back. And that's when it started." – Joe Greene

• "It brought Pittsburgh into the picture of football teams in the National Football League that, 'OK, you have to deal with us now.'" – Joe Greene on the victory in Super Bowl IX

• "You look up to that guy and you don't want to let him down. With Joe Greene, I found that leadership really does matter." – Jack Ham

• "It changed our lives a lot. It changed Joe's personality a lot. Because so many kids were looking up to him, he decided he really wanted to be a role model for the kids." – Agnes Greene on the Coca-Cola commercial