Tonight on HBO’s Real Sports With Bryant Gumbel, correspondent Jon Frankel will preview a segment that will air October 21 about the domestic violence scandal plaguing the NFL and a possible link to repeated head injuries sustained playing the game. Frankel sits down with the widow of former San Diego Chargers safety Paul Oliver to discuss her husband’s acts of domestic violence and how, following his suicide a year ago, experts from Boston University discovered Oliver had an advanced form of chronic traumatic encephalopathy (CTE), which has been linked to mood swings and violence. Watch the clip above.