candid admission from a living legend. It has parents and fans asking a whole new set of questions about the possibility punishing consequences of football for children and for their heros. Tony... See More
candid admission from a living legend. It has parents and fans asking a whole new set of questions about the possibility punishing consequences of football for children and for their heros. Tony dorsett, football icon, seemly invincible has come forward to describe a brutal diagnosis. Abc's senior national correspondent jim avila. Reporter: The breezy charisma and movie star smile of hall of famer tony dorsett, literally knocked from his face by hit after hit in the nfl. They call that a knockout. Reporter: This is the remembers most. Watch again. It knocks his chin strap into the air and left dorsett sprawled on the turf for 15 minutes. I mean he just blew me up. It was like a freight train hitting a volkswagen. Reporter: But minutes later dorsett was back in the game, one of the countless concussions he suffered. Today at age 59 he's clinically depressed, short tempered and even suicidal. I'm too smart of a person to take my life but it's crossed my mind. Reporter: So worried dorsett and 8 other former nfl players volunteered for a break through study at ucla which this week said what he feared most, he has the signs of cte from hits that carry the power of a sledge hammer. Until how doctors have only seen damage of this after death in the autopsy of football's most famous. It has the living like jim McMAHON AND EVEN BRETT FAVRE Suffering symptoms as a newly diagnosed tony dorsett. Who are you? Who are you becoming. Reporter: Finally he has that diagnosis and while still alive. For us to be able to diagnose it in the living, that's the only hope we have of possibly helping them and treating them. Reporter: A first step to replacing what so many heros of the game have lost. Jim avila, abc news, washington.
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