“Look, I’m still in tiptop physical shape and can probably run a marathon,” Hoffman said, the words tumbling out of a mouth missing a tooth that was knocked out in a street fight. “It’s my brain that keeps me from being a productive member of society. I’m physically very strong, but I’m mentally so weak. Something is wrong with me. I don’t know what it is, but I used to be normal, you know?

“I’m confident — well, I’m pretty sure — that football had something to do with it.”

Football’s toll on its participants is well established. We know about dozens of former N.F.L. players who were left with severe brain damage from repeated blows to the head. Their stories often contain disturbingly similar details — depression, substance abuse, memory loss, dementia — and their brain damage was always revealed posthumously.

But there are many more former players out there wondering if they are football’s next casualties. Most of those players are not famous. Most never made a dime off the game. They are relatively anonymous men who played the sport in college and only later, for some reason or another, have found themselves struggling in life.

Just like their N.F.L. counterparts, Hoffman and those former college players have been left to wonder: Did football do this? Are the hits to the head I took the reason for my decline? Or would I be in this condition even if I’d never played a down?

They might never know the answer, because a definitive answer might not exist.

Hoffman blames football for scrambling his brain, but at this point it is impossible to disentangle what could be football-related brain injuries from his subsequent drug use and possibly genetic mental illness. He simply cannot be sure. No one can.

… and not see Mark Richt’s Paul Oliver Network in a different, less cynical way.  I know I can’t.