The head of the National Football League, Roger Goodell, admitted in a video statement on Friday that the league was slow to hear the protests of institutional racism from some of its black players. Goodell said the league acknowledges "the systematic oppression" of black people and encourages "all to speak out and peacefully protest."

The NFL has been a flashpoint for protests over police violence ever since Colin Kaepernick began kneeling during the national anthem before games.