FILE - In this Oct. 2, 2016, file photo, then-San Francisco 49ers quarterback Colin Kaepernick kneels during the national anthem before an NFL football game against the Dallas Cowboys, in Santa Clara, Calif. Ex-NFL player Colin Kaepernick helped start a wave of protests by kneeling during the national anthem to raise awareness to police brutality, racial inequality and other social issues. Big-name entertainers believe social injustice needs to be addressed during the Super Bowl and are ensuring the topic that ignited a political firestorm and engulfed the NFL will be in the spotlight. (AP Photo/Marcio Jose Sanchez, File)

FILE - San Francisco 49ers outside linebacker Eli Harold, left, quarterback Colin Kaepernick, center, and safety Eric Reid kneel during the national anthem before an NFL football game against the Dallas Cowboys in Santa Clara, Calif., Sunday, Oct. 2, 2016. From gambling suspensions of Paul Hornung and Alex Karras in the 1960s to Colin Kaepernick and other players kneeling during the national anthem, the NFL always seems to overcome controversies. (AP Photo/Marcio Jose Sanchez, File)