The NFL lost a legend Thursday.

The Steelers announced that owner, icon and Hall of Famer Dan Rooney died. He was 84.

Rooney, the father of the Rooney Rule, was inducted into the Pro Football Hall of Fame in 2000. His impact went beyond the Rooney Rule, which made it a requirement for teams to interview at least one minority candidate for vacant head coaching positions. He was one of the most influential figures in the entire league and, of course, with the Steelers.

He worked for the team since 1955. In 1975, he became president of the franchise. Two years before, he became chairman of the league's expansion committee. That committee added two franchises, Seattle and Tampa Bay. He was the Steelers' controlling owner from 1988 to 2003. From 2003-2017, he was the team's chairman. He was even the U.S. ambassador to Ireland for more than three years.

This quote, from a Sports Illustrated story that ran in 1979, really gets at Rooney's approach:

"I stay in the background," he said. "A lot of owners in football think they have to say something profound, particularly to explain a win or a loss. I think the less you say, the better off you are. My job here is to make everyone else's job easier. The Steeler players get the recognition, and that's the way it should be. That's better than having Chuck Noll or Dan Rooney get it. The players are the characters, if you look at football in the entertainment sense."

Those who knew him shared their thoughts on Twitter:

NFL commissioner Roger Goodell released a statement, in which he called Rooney "one of the finest men in the history of our game." His entire statement is below:

"Few men have contributed as much to the National Football League as Dan Rooney. A member of the Pro Football Hall of Fame, he was one of the finest men in the history of our game and it was a privilege to work alongside him for so many years. Dan's dedication to the game, to the players and coaches, to his beloved Pittsburgh, and to Steelers fans everywhere was unparalleled. He was a role model and trusted colleague to commissioners since Bert Bell, countless NFL owners, and so many others in and out of the NFL. A voice of reason on a wide range of topics, including diversity and labor relations, Dan always had the league's best interests at heart. For my part, Dan's friendship and counsel were both inspiring and irreplaceable. My heart goes out to Patricia, Art, and the entire Rooney family on the loss of this extraordinary man."

Shortly after Rooney's death, former Steelers coach Bill Cowher told a fitting anecdote involving Rooney, Steelers fans and pizza: