San Francisco 49ers rookie LB Chris Borland retires at age 24 over head trauma concerns – New York Daily News
Chris Borland retires from NFL at just 24 years old, makes his own sense of head injuries – New York Daily News
Chris Borland: Young American football player retires over concerns of brain injuries, The Independent
49ers' Chris Borland becomes latest young NFL star to retire early - Cincy Jungle
San Francisco's Borland joins recent list of early retirees in NFL, National Sports
Chris Borland finding life after football isn't easy
Chris Borland's early NFL retirement has led to impact off the field - BVM Sports
Chris Borland quit NFL, now helps those in retirement
NFL star Chris Borland quits over head injury concerns - CBS News
NFL star Chris Borland quits over head injury concerns
24-year-old NFL player quits over concussion worries
49ers ex-linebacker Chris Borland salutes Pat Tillman
Former Badgers NFL linebacker retires to become mental health advocate
49ers' Borland retires after rookie year over head trauma fears – Santa Cruz Sentinel
Chris Borland - Wikipedia