after this hit by 49er kennan turner, super bowl mvp otis anderson was never the same.s one of 78 former players alleging the league covered up risks of repeated head injuries. >> fans, we love the contact, we want to see the hits. >> reporter: experts say the longer players play, the greater the risks. >> you look at our players here, they may sustain multiple concussions, they may not tell anybody, maybe play professional or semi pro, those all add up. each blow can add a little more damage to the brain. >> reporter: helmet maker riddel is also named in the suit. >> as i was walking off the sideline was moving and i remember staying out for a series or two and going back in the game. >> reporter: some fans say players know the risks. others blame team owners. >> they had to know. there's no doubt about it. like i said, i'm with the players, i'm for the players. >> it's a huge billion dollar business, it's got to be a blow. >> reporter: the nfl said it will contest the allegations. riddel had no comment. trainers here at diablo valley college say they test each player

the miami dolphins, former new york giants running back rodney hampton and former super bowl mvp otis anderson. the manufacturers of nfl helmets is also a defendant in this case. i'm joined by the editor of profootballtalk.com. a pleasure to have you on, certainly not under these circumstances this. concussion thing, talking about it so much, and now you've got this lawsuit here. >> well, and this is one of the things that i think we've all been anticipating as we've learned more and more about concussions. there's been debate and argument about how much the nfl knew, when they knew it. there's been some studies in the past that a lot of people criticized, but the real question is going to be from a statute of limitations standpoint can these retired players come forward today and file this lawsuit? i think a lot of people have understood that there were risks to playing football, risks of suffering head injury. it's only in the past few years that we've really understood what those risks fully, are but i think for years and years there's been an understanding if you play football you're going