NEW ORLEANS — As a student, Donald Trump played high school football. As a business baron, he owned a team in an upstart rival to the NFL and then sued the established league. As president, he denigrated pros who took a knee during the national anthem as part of a social justice movement.

Donald Trump on Sunday will become the first sitting U.S. president to attend a Super Bowl – but the former reality television star has a long and complicated history with the sport of football.

Trump took issue with players kneeling during the national anthem to protest social or racial injustice. That movement began in 2016 with then-49ers quarterback Colin Kaepernick taking a knee during “The Star-Spangled Banner” during an exhibition game in Denver.