Transcript for Dan Marino Withdraws Name in NFL Concussion Lawsuit
Now to one of footballs most famous faces and a lot of questions about whether he would join a major lawsuit against the NFL over major concussions. Dan Marino revealing he's out. Why the shift? ABC's Jim Avila on the new twist tonight. Reporter: Marine knee backing out without explanation. The suit charges the NFL allowing players to block tackle, butt, spear, ram and or injury opposing players with their helmeted head. But Marino who played 17 years in the NFL isn't known for concussio concussions. He suffered only two. Why think about suing? It could be a case of just in case symptoms show up later. It shows us that every single player who has played the game is thinking about this, is wondering about it and worried about it. It is something because it is prevasive. Reporter: At the university of Alabama Birmingham an evident to update helmet tests that haven't changed since 1969 tracking the head-on force and the twisting force in rotation that causes more damage to the player. That can cause another source of trauma and it's been shown to be an important source of concussions. Reporter: From quarterback to linebacker concerned for their health.
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