Why the NFL needs to worry about Chris Borland
Chris Borland retires from NFL at just 24 years old, makes his own sense of head injuries – New York Daily News
Chris Borland to retire from NFL, fearing concussions
Expect more early NFL retirements, says former player
Chris Borland's Concussion Concerns, Retirement Are Latest Big Blows To NFL Business
San Francisco 49ers Chris Borland Retiring at 24, News
I AM IN PAIN HEAD TO TOE - PressReader
49ers ex-linebacker Chris Borland salutes Pat Tillman
Chris Borland stuns 49ers with retirement announcement