“I think he will join the folks from [the Tokyo Olympics in] 1968, Carlos and Smith, for being out in front of the movement and suffering for those political decisions he made,” said Trimbur, author of the book Come Out Swinging: The Changing World of Boxing in Gleason’s Gym about minority youth who take up boxing after leaving prison.

“I think he will take a place alongside Ali in terms of saying, ‘My conscience does not allow me to continue to not take a stand against racist police violence’.

“Ali, Carlos and Smith and Kareem Abdul Jabbar, they are really remembered as solo figures and larger than life in terms of personality and what I hope for Kaepernick is for him to be remembered as the person who triggered a movement. Who really triggered mass numbers of people to take action, and athletes to really consider their place in society and to realise the power that they have.”

US Anthem protests: NFL, BLM and what preceded Kaepernick

Brady is making his 10th Super Bowl appearance, Mahomes his second while Kaepernick has one to his name when the 49ers were beaten by Baltimore in the 2013 showcase.

The mural is likely the closest Kaepernick will get to another Super Bowl, his career derailed by owners reluctant to sign him after he was vilified by former President Donald Trump as “unpatriotic”.

Ben & Jerry’s head of global activism Chris Miller said Kaepernick showed that he was “on the right side of history”. Miller and Goodell are emboldened to sigh and regret because taking a knee is now a global movement with athletes across the world, including football players in the English Premier League, performing the ritual before games.

In 2016, when they were cowering under a far right agenda, America was largely silent. Kaepernick was forgotten and attempts to resurrect his career were blocked at every turn. At 33 and with four years away from the NFL, Trimbur said a Kaepernick comeback was unlikely as he appears to shift his focus to social activism.

“I think with the protests and the increased politicisation of sport and athletes, we sort of dropped that question and stopped asking it,” said Trimbur on whether Kaepernick would ever make a comeback.

“I don’t think he’s going to play. I think now it is too many years out. For a while he was training really vigorously and he was keeping up on the latest workouts and he was really in tip-top shape with the hope, it seemed, of returning to the NFL.”

Athlete protest ban at odds with Olympic history

“I think too much time has gone by and it’s really hard to keep your body in that kind of competition shape without a team, especially at quarterback,” Trimbur said. “And I don’t know the extent to which this other life he has created for himself has taken over as a priority because, you know, he’s done so much in six or seven years.

“He really has completely changed the political terrain for athletes in the US but also internationally. And I think he suffered greatly for early protests that he engaged in but in a way paved the way for athletes after him to protest.

“I don’t know if there was a point in which he decided that his heart was really in the political struggle for black and brown people in the United States. [After the Atlanta workout], it really did feel like there wasn’t going to be discussion about him playing.”

Trimbur said the vile racial politics that have always hung over American society broke out of its shell after Trump took over as president. Those from the far right who had reluctantly hid their positions for so many years felt empowered by Trump’s rhetoric, she said.

“Donald Trump did such a good job of creating an environment of fear and creating an environment of scarcity that somehow people of colour were seen as responsible for it,” said Trimbur. “So I think it did set things back a very, very long time and I think that’s something that this country has to reckon with over the years to come.

“Kaepernick was out there alone for a really, really long time and then other athletes started in that first season taking a knee. But people took a knee at every level of play in the United State, at collegiate level, at high school, at the youth level. And they received death threats.

“The amount of racial threats that nine-year-olds took in this country, to take a knee, it’s just staggering. and the bravery and courage of those athletes week after week, saying, ‘I’m 10, and I’m going to take a knee because it’s my right and it’s what I believe in’.

“I find that inspiring and I hope that will be a base on which the real hard work of anti-racism can really start.”

The concept that sport should be separate from politics is a myth that has been destroyed time and again even before Carlos and Smith raised their fists in a black power podium salute at the 1968 Tokyo Games.

The global sports community, on the contrary, can help to create tolerance and acceptance at all levels and Trimbur said the political aspects can be of benefit.

“What sport needs to do is really leverage the convivial moments,” she said. “Really figure out a way at community level to build up on those moments – cross-racial, cross-class, cross-gender – that really support these convivial spaces in which people experience joy together and people compete with each other and people depend on each other.

“Sports has so much power in structuring people’s consciousness if leveraged in the right way. The wrong way is how it’s been leveraged at political rallies that use collegiate football, American football as ways to really get crowds of fascist-type participants frothing at the mouth.

“That’s the way sport has been used by our former president. It’s really been used to create fear and to exclude but I think just as it was acceptable under Trump’s administration in doing that, it can do the opposite, and I think it really is those moments of conviviality.”