With his decision two summers ago to not stand for the national anthem, Colin Kaepernick became the face of a protest movement in the NFL against racial injustice and police brutality.

Now, the former quarterback has become a face of one of the most iconic advertising campaigns in the history of sports: Nike's "Just Do It" campaign.

An early image from the campaign made its debut on Monday with a tweet from Kaepernick. The advertisement shows a black-and-white image of the former San Francisco 49ers quarterback. The text on top of the image reads: "Believe in something. Even if it means sacrificing everything."

As part of the campaign commemorating the 30^th anniversary of "Just Do It," Nike will produce new Kaepernick apparel, including a shoe and a T-shirt, according to The New York Times. The company — which supplies game-day uniforms and sideline apparel for the league's 32 teams — will also donate to Kaepernick's "Know Your Rights" campaign, according to the Times.

News of Kaepernick's role in the campaign comes at a delicate moment for the NFL. With the 2018 regular season set to begin on Thursday, the league and its players union remain locked in a stalemate over a controversial national anthem policy ratified by team owners in May. The policy gave players the option to stay in the locker room during the anthem, but required them to stand if on the field or face possible discipline by their teams.

The policy was put on hold in July, leaving the NFL without a resolution to what's become one of the most polarizing issues in sports. The player protests have drawn frequent criticism from President Trump, who in a speech last September said, "Wouldn't you love to see one of these NFL owners, when somebody disrespects our flag, to say, 'Get that son of a bitch off the field right now?' "

In an interview shortly after his protest began, Kaepernick told NFL media, "To me, this is bigger than football and it would be selfish on my part to look the other way." Kaepernick has not played in the NFL since parting ways with the 49ers at the end of the 2016 season. He alleges that the NFL colluded to deny him a contract as punishment for his role in the player protests. Last week, an arbitrator ruled that his grievance against the league merits a formal hearing.

The NFL has yet to issue a response to the ad campaign, but some in the league have said they believe the protests have damaged the popularity of professional football. Nike, for its part, has previously said that it "supports athletes and their right to freedom of expression on issues that are of great importance to our society."

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