(CBSDFW.COM/AP/CBS NEWS) – Colin Kaepernick, the out-of-work quarterback suing NFL owners for allegedly colluding to keep him out of the league, is a part of Nike’s latest advertising campaign.

Kaepernick became a controversial figure for his taking a knee to protest social injustice during the national anthem before NFL games.

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The new ad, which Kaepernick shared on social media Monday afternoon, features the message: “Believe in something. Even if it means sacrificing everything.”

Nike signed Kaepernick in 2011 and kept him on its endorsement roster over the years, ESPN reported. The company had not used him in the past two years.

NFL owners approved a new policy in May requiring players to either stand during the anthem or remain off the field.

That policy has yet to go into effect as negotiations between the league and the players’ union over the policy continue.

Several players raised their fists, kneeled or stayed off the field at preseason games over the past several weeks.

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Nike did not immediately respond to requests for comment.

An arbitrator is sending Kaepernick’s grievance with the NFL to trial, denying the league’s request to throw out the quarterback’s claims that owners conspired to keep him out of the league because of his protests of social injustice.

Kaepernick’s lawyer Mark Geragos tweeted a picture last Thursday of a ruling by arbitrator Stephen B. Burbank. The NFL declined a request for comment.

Kaepernick, who led the San Francisco 49ers to a Super Bowl appearance and NFC championship game in consecutive seasons, argues that owners have colluded to keep him off any NFL roster since he hit free agency in 2017.

Burbank’s decision means there was sufficient evidence of collusion to keep Kaepernick’s case going.

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(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)