The NFL announced that legendary coach and Hall of Famer John Madden passed away on Tuesday, December 28.

His death came suddenly and unexpectedly, and no cause has been announced. Madden became an iconic part of the NFL experience, first as a coach and later as a broadcaster. Madden was 85.

Madden coached the Oakland Raiders beginning as a linebacker coach in 1967. He became the head coach of the franchise in 1969. He spent ten years as the head coach, guiding the Raiders to post-season appearances in all but two seasons. Madden holds the league record for regular-season wins but struggled to get wins in the post-season. The Raiders won Super Bowl XI under Madden but lost five AFL Championship games and were eliminated in the Divisional round in 1972.

“On behalf of the entire NFL family, we extend our condolences to Virginia, Mike, Joe, and their families,” said NFL Commissioner Roger Goodell in a press release announcing Madden’s death. “We all know him as the Hall of Fame coach of the Oakland Raiders and broadcaster who worked for every major network, but more than anything, he was a devoted husband, father, and grandfather.

“Nobody loved football more than Coach. He was football. He was an incredible sounding board to me and so many others. There will never be another John Madden, and we will forever be indebted to him for all he did to make football and the NFL what it is today.”

Following his retirement from coaching in 1979, CBS hired Madden as a color commentator. Madden became a regular commentator and covered Monday Night Football until his retirement in 2009. He popularized the use of the telecaster, a device that allowed the former coach to superimpose his light pen on the screen to illustrate how a play broke down in real-time. The technology is now common in all sports.

“He was so much more than just football — a keen observer of everything around him and a man who could carry on a smart conversation about hundreds and hundreds of topics,” said former co-broadcaster Al Michaels upon hearing of the passing of Madden. “A dear friend, a wonderful partner in the broadcast booth, and a man who brought so much joy to so many people, I’ll miss him enormously.”

In 1988, Madden lent his name and voice to the video game series that continues today. The Madden video game franchise by EA Games is the best-selling sports game in history and one of only two games to have sold more than 100 million copies worldwide. Madden viewed the game as an educational tool that helped introduce football concepts to young people who were not players.

“If you knew John, he made your life better. For me, he was a trusted confidant, advisor, teacher, and above all, a very dear friend. When he walked into the room, it was a better day. When he talked, you listened, and you learned. When he laughed, everyone in the room laughed. And when he got back on the bus to leave, you always wanted more. You were always looking forward to his next visit,” said Cowboys owner and CEO Jerry Jones in a statement on the passing of Madden.

His death comes only days after the release of “All-Madden,” an NFL Films documentary that chronicled the life of the legendary coach and broadcaster. The documentary aired on December 24.