The opening of “The Fragile Teenage Brain,” neuroscientist Jonah Lehrer’s devastating Grantland examination of football’s concussion problem, a plague not only on the NFL but also on high schoolers playing under the lights on Friday nights:

“If the sport of football ever dies, it will die from the outside in. It won’t be undone by a labor lockout or a broken business model — football owners know how to make money. Instead, the death will start with those furthest from the paychecks, the unpaid high school athletes playing on Friday nights. It will begin with nervous parents reading about brain trauma, with doctors warning about the physics of soft tissue smashing into hard bone, with coaches forced to bench stars for an entire season because of a single concussion. The stadiums will still be full on Sunday, the professionals will still play, the profits will continue. But the sport will be sick.

The sickness will be rooted in football’s tragic flaw, which is that it inflicts concussions on its players with devastating frequency.”

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Colt McCoy gets concussion, returns to game two plays later: