BERKELEY, Calif. — San Francisco 49ers linebacker Chris Borland, one of the NFL’s top rookies the past season, told “Outside the Lines” on Monday that he is retiring because of concerns about the long-term effects of repetitive head trauma.
BERKELEY, Calif. — San Francisco 49ers linebacker Chris Borland, one of the NFL’s top rookies the past season, told “Outside the Lines” on Monday that he is retiring because of concerns about the long-term effects of repetitive head trauma.