In 2013, Tony Dorsett was diagnosed with chronic traumatic encephalopathy, a degenerative disease of the brain linked to repeated hits to the head.
The symptoms include memory loss and depression.
The Pro Football Hall of Fame running back and Cowboys legend provided a sad health update Saturday before a 25th anniversary celebration of Dallas' 1992 Super Bowl team.
"I'm fighting CTE," he said. "I have good days and I have bad days. The unfortunate thing sometimes is I have more bad than good. It is what it is. I'm trying to maintain and handle it.