The NFL has an extremely ugly history with concussions. I won't rehash it all here, but in broad strokes, the American football organization spent years denying a link between head injuries sustained by players and the devastating long-term effects, was eventually sued by more than 4,500 players for negligence and fraudulent concealment, and settled the suit for nearly a billion dollars in 2013.
The Madden football series, for their part, included concussions in the games for a few years (in part due to John Madden's insistence), though a less-specific description of "head injury" replaced the term in Madden 13.
