Last November Kaepernick filed a grievance against the National Football League in which he alleged that franchise owners colluded to keep him from signing with another team.
The former quarterback was the first in the National Football League to kneel in protest against racism.
The simple black and white ad showcases Colin Kaepernick's face with the words "Believe in something".
President Trump has criticized the kneeling protest on multiple occasions.
"Having a huge company back him could be a controversial reason for this company, but they're not afraid", said Williams, who is sponsored by Nike.
The former 49ers quarterback started kneeling during the "Star-Spangled Banner" in August 2016 as a means of protesting racial inequality and police brutality.
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Kyl represented Arizona in the Senate from 1995 to 2013. "So we went out there and there was nothing left", Jacob said. Cindy McCain quickly offered her support , calling Kyl "a dear friend of mine and John's".
Nike, who confirmed on Monday that Kaepernick was part of the campaign and called him "one of the inspirational athletes of his generation", did not immediately respond to requests for comment on Tuesday.
At a rally in Alabama previous year, Trump said team owners should "get that son of a b-tch off the field" if a player knelt in protest of injustice during the anthem.
The ad has garnered an increase of Nike brand mentions by 135% compared with the previous week, with a mix of positive and negative mentions, according to social media analytics firm Talkwalker.
He then celebrated the decision he had made - and encouraged others to do the same.