There have already been several earlier than expected, health-related NFL retirements that seemed like reactions (at least in part) to concussion risks. Yesterday, San Francisco 49er Chris Borland announced that he was quitting the game, and he left no doubt about the reason: “I think I’d have to take on some risks that, as a person, I don’t want to take on.” And Borland has only played one year (and that year was a major success). Grantland’s Bill Barnwell calls the move the definition of tough: “What makes it so different is that it’s a proactive retirement.” (Borland is leaving a lot of money on the table so he’ll be more likely to remember there is a table.)

+ WaPo: Is Chris Borland’s retirement the beginning of the end for the NFL?