Nick Buoniconti (85), with Dolphins official Nat Moore in 2015. The Hall of Famer died this week. (Wilfredo Lee/AP)

Nick Buoniconti, the Hall of Fame linebacker from the Miami Dolphins undefeated championship team who spoke of his decline from dementia in recent years, died Tuesday night at the age of 78, the team announced.

The 14-year veteran, a 2001 inductee into the Pro Football Hall of Fame, was part of the Dolphins’ 1972 team, the only NFL team to go undefeated and win a Super Bowl. He spent the first seven seasons of his career with the Patriots, although his greatest fame came with the Dolphins, with whom he won two Super Bowls He later spent years as a co-host of the HBO program, “Inside the NFL.”

Buoniconti earlier this week had been admitted to a hospice facility, according to the Palm Beach Post. Because he believed that chronic traumatic encephalopathy from hits to the head over the course of decades of football had “taken my life away,” he requested that his brain be donated to the Boston University CTE Center.

The Center said that Buoniconti and his wife, Lynn, also pledged to establish a research fund to accelerate research on the diagnosis, care and treatment of CTE.

“Nick was one of a kind, an NFL Hall of Fame legend whose impact on the field was remarkable, but whose impact off the field was even more so. . . . ,” the Center said in a statement. “In his last years, Nick courageously fought the greatest battle of his life against a devastating and untreatable neurodegenerative disease that was most likely CTE or chronic traumatic encephalopathy.”

In the years after he retired from the NFL in 1976 at the age of 36, Buoniconti obtained a law degree and became an advocate for research into cures for paralysis, establishing the Miami Project to Cure Paralysis and the Buoniconti Fund after his son, Marc, was confined to a wheelchair because of a neck injury he sustained playing in a football game for The Citadel.

Two years ago, Buoniconti lent his name to another project, one aimed at the study of CTE and the role that repeat subconcussive hits play in neurocognitive decline. This, too, was an extremely personal project because, like so many other football players, he was realizing that something wasn’t quite right with him.

“I feel lost,” he told S.L. Price in a MMQB story, describing his cognitive decline, memory loss and struggle to complete basic tasks like pulling on a shirt and tie. “I feel like a child.”

In a statement at that time to the Miami Herald, his son Marc said, “This has been my dad’s reality for a while now, and it’s been a frustrating and heartbreaking journey. To see him like this after all he’s done to help others breaks my heart and makes me want to do everything I can to find some answers for him and the countless other athletes dealing with these issues.”

Marc Buoniconti said in a statement on Wednesday that his father “was truly larger than life.”

“My dad has been my hero and represents what I have always aspired to be; a leader, a mentor and a champion,” the younger Buoniconti said. “He selflessly gave all to football, to his family and to those who are less fortunate. He made a promise to me that turned into a revolution in paralysis research. We can best honor his dedication and endless commitment by continuing with our work until that promise is fulfilled and a cure is found.”

Buoniconti also participated in an HBO documentary that showed in stark video just how he struggled with everyday life. “We’re both, in a way, paralyzed,” he said, referring to his son. “I’m paralyzed because I can’t do the basic things in life. It’s not pleasant to think about where my life is going to take me.”

He was “positive,” he said, “that . . . football caused this” decline, and admitted that he played much of the Super Bowl in a daze after being knocked out.

“When we were growing up, football gave everything to us,” Marc told HBO. “And then look at what it did to me. And now look at what it’s doing to him. I mean, do you love the game? Hate the game? Do you love it and hate it?”


Buoniconti after his 2001 Hall of Fame enshrinement. (Mark Duncan/AP)

Last year, Buoniconti urged parents to allow their children to play only flag football until they’re 14.

“I made a mistake starting tackle football at 9 years old,” he said. “Now, CTE has taken my life away. Youth tackle football is all risk and no reward.”

Rick Bernstein, HBO Sports’ executive producer, praised Buoniconti for living “an extraordinary life,” according to the Palm Beach Post.

“He accomplished virtually everything he set his sights on in life,” Bernstein said. “He was a trailblazer. Pairing him with Len Dawson on ‘Inside the NFL’ for 23 years is an unforgettable part of football television history. And then having the blessing of Nick and his wife, Lynn, to chronicle his lifelong journey and produce a documentary earlier this year is an important part of our heritage at HBO Sports. It was vintage Nick Buoniconti: honest, raw and to the point. Everybody at HBO Sports is grateful to have had Nick as a friend, colleague and part of our family.”

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Perspective: Roger Goodell doesn’t care about integrity or consistency. The Robert Kraft case proves it.