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San Antonio Spurs head coach Gregg Popovich said former San Francisco 49ers quarterback Colin Kaepernick, who has received much criticism for protesting racial inequality and social injustice during the national anthem in the 2016 NFL season, will be celebrated someday.

Marc J. Spears of The Undefeated provided the quotes:

Muhammad Ali refused to serve in the Vietnam War, was arrested and stripped of his heavyweight title. Boxing associations refused to grant him a license, and he didn't fight for three-and-a-half years.

Years later, he received the Presidential Medal of Freedom. The Louisville, Kentucky, airport is named after him.

Tommie Smith and John Carlos gave the Black Power salute on the medal stand at the 1968 Summer Olympics to protest racial inequality. Smith and Carlos took gold and bronze, respectively, in the 200 meters.

They were eventually expelled from the rest of the Games. Forty years later, they accepted the Arthur Ashe Award for Courage at the ESPYs.

The 31-year-old Kaepernick has been out of the NFL for two years, and he has filed a collusion case against the NFL that will go to trial.

Regardless of the result, it's very likely that his career is over. But it's certainly possible that Popovich is right and that history will look back and place Kaepernick alongside other esteemed athletes who sacrificed everything for their beliefs.