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But then a wave of controversy was unleashed when he sat down during the national anthem of a 2016 preseason game to take a stand against police brutality and racial injustice. Since then, Kaepernick has become an outspoken advocate for social justice. And along the way he became one of the most admired and most hated people in sports.
NFL Commissioner Roger Goodell released a statement in early June condemning systematic racism and apologizing for "not listening to NFL players earlier" when they tried to address racial injustice. His statement on social media drew comparisons to Kaepernick, with many calling for Goodell to apologize to the former Niners quarterback.
Here's a timeline of Kaepernick's time with the 49ers.
November 11, 2012
Colin Kaepernick replaced Alex Smith after the quarterback suffered a concussion during a game against the Rams. Kaepernick remained the starting quarterback the rest of the season.
January, 12, 2013
Kaepernick had a career day in his first postseason start. He passed for passed for two touchdowns and ran for two more as the 49ers pummeled the Green Bay Packers. Kaepernick rushed for 181 yards, a team postseason record at the time.
February 3, 2013
Kaepernick threw for 302 yards in a 31-34 Super Bowl XLVII loss to the Baltimore Ravens. The 49ers scored 17 unanswered points to overcome a big deficit and were poised for a dramatic victory, but a late game drive came up a few yards short of the end zone.
June 4, 2014
The 49ers gave Kaepernick a $126 million contract extension, but the team lost its dominance and missed the playoffs. Head coach Jim Harbaugh left after the season. Kaepernick struggled under two different coaches.
August 26, 2016
A beat reporter takes a picture that shows 49ers quarterback Colin Kaepernick sitting on a bench while his teammates stand during the national anthem of an NFL preseason game. "It is to protest the injustices that are happening in America, the oppression that is happening in America," Kaepernick told reporters after the game.
September 1, 2016
Keapernick continued his protest but after speaking to U.S. Army veteran Nate Boyer, Kaepernick decided to kneel instead of sitting down as a sign of respect for military personnel. His 49ers teammate Eric Reid joined the protest. Kaepernick pledged to donate $1 million to community groups and social justice causes throughout the country.
September 11, 2016
Other NFL players begin kneeling or raising a fist during the national anthem as a sign of protest.
September 22, 2016
Kaepernick appears on the cover of Time magazine for a story on patriotism and protests. Kaepernick is voted most disliked NFL player but his jersey becomes a top seller.
January 1, 2017
Kaepernick played his last game as an NFL player in a loss to Seattle.
March 3, 2017
Kaepernick opted out of his contract with the San Francisco 49ers. Even though he is a free agent, Kaepernick is not signed by any NFL team during the off-season.
August 12, 2017
Other players, including the Oakland Raiders' Marshawn Lynch, continue to protest injustices by sitting or kneeling during the national anthem.
September 22, 2017
President Donald Trump calls on NFL owners to fire players who won't stand for the national anthem. "Wouldn't you love to see one of these NFL owners, when somebody disrespects our flag, get that (expletive) off the field right now," said Trump during a rally.
September 25, 2017
NFL teams and the Golden State Warriors respond to President Trump's rhetoric. Several owners kneel or lock arms with players as a show of unity during the national anthem.
October 8, 2017
Vice President Mike Pence leaves the Indianapolis Colts game after the players kneel during the anthem. Some owners threaten players by stating that those who don't stand for the national anthem won't play in the game.
October 15, 2017
Kaepernick files a grievance against the NFL in which he accused owners of colluding by not signing him and keeping him out of the NFL.
November 13, 2017
Kaepernick is named "Citizen of the Year" by GQ Magazine. He is later named a finalist for Time's "Person of the Year".
December 3, 2017
The ACLU honored Kaepernick by giving him the Courageous Advocate award. "We all have an obligation, no matter the risk and regardless of reward, to stand up for our fellow men and women who are being oppressed, with the understanding that human rights cannot be compromised," said Kaepernick during the ceremony.
April 21, 2018
Amnesty International gives Kaepernick its Ambassador of Conscience award.
August 30, 2018
An arbitrator denied the NFL's request to dismiss Kaepernick's complaint that NFL owners have colluded to keep him out of professional football. Kaepernick's lawsuit against the league is allowed to move forward.
September 3, 2018
Nike reveals its new advertising campaign featuring Kaepernick with the slogan "Believe in something, Even if it means sacrificing everything."
November 12, 2019
The NFL sets up for a private workout for Kaepernick and invites all 32 teams, but Kaepernick skipped the tryout over concerns the NFL asked him to sign a liability waiver. Kaepernick remains unsigned.
December 23, 2019
Debut of Colin Kaepernick x Nike Air Force 1. The shoe has a portrait of Kaepernick on the heel and the date he began his protest on the sole.
Get the latest on former 49er quarterback Colin Kaepernick here.
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