Colin Kaepernick has filed a lawsuit against America's National Football League, claiming team owners are conspiring not to hire him because of his demonstrations.
The profile of the football player rose dramatically in 2016 after he protested the national anthem during a match with his former team - the San Francisco 49ers - by kneeling.
His action was to demonstrate against racial injustice in America, and quickly other players followed suit - a movement that gained momentum after it was heavily criticised by President Donald Trump.
However Kaepernick is now a free agent, having left the 49ers, and lawyers for the quarter-back released a statement on Sunday to announce a motion had been filed.
The lawsuit claims team owners have colluded to avoid hiring him, saying peaceful protest should not be punished.
Robert Kraft, the owner of the New England Patriots - has commented publicly to deny this, saying he'd never heard any talk about exclusion in regard to Kaepernick.