As the National Football League season culminates with Sunday’s Super Bowl, the player who had the most impact on the season never actually set foot on the field. He is, of course, former San Francisco 49ers quarterback Colin Kaepernick, who has been emulated by fellow African American players and unofficially banned by coaches and executives for his activism.

In a 2016 preseason game, Kaepernick knelt during the national anthem to protest fatal police shootings of unarmed black men. This season, the gesture spread throughout the league. President Trump railed against the protesting players in profane terms, demanding they be fired, and Kaepernick remained unsigned even as a backup quarterback, despite his previous success.

Paying such a high price for his principled stance, Kaepernick grew into a legitimate civil rights icon. Sports Illustrated bestowed on him an award named for Muhammad Ali, who had been exiled from boxing for his draft resistance during the Vietnam War. The New Yorker unveiled a cover depicting Martin Luther King Jr. taking a knee alongside Kaepernick and another player-activist, Michael Bennett of the Seattle Seahawks.

But as Americans celebrate Kaepernick, they continue to overlook the first African American quarterback who fell victim to a similar punishment for fighting racism: James “Shack” Harris, who was the star quarterback for the Los Angeles Rams in the mid-1970s — until he wasn’t.

In pro football’s portion of the civil rights struggle, the last positions to be desegregated were center, middle linebacker and quarterback. Those three spots, not coincidentally, required the greatest intellectual acumen, because they involved calling the blocking assignments (center), defensive alignment (middle linebacker) and the entire offense (quarterback). In the late 1960s, white supremacist perceptions still kept blacks from quarterbacking an NFL team. No black player could possibly be smart enough, have the required strength of character or possibly give orders to white teammates.

From day one, Harris seemed destined to break this barrier.

A child of the black middle class, with a minister for a father and a nurse for a mother, Harris had the athletic, cerebral and temperamental equipment necessary for success. He had been a stellar student who cherished the family’s 2,000-page dictionary. Athletically, he set every passing record at Grambling State University, working with a group of future pro stars.

Very purposefully, Harris’s college coach, the legendary Eddie Robinson, developed him specifically as a drop-back, pro-style passer so he could shatter the color barrier for NFL quarterbacks.

Yet Harris languished until the Buffalo Bills selected him in the eighth round of the draft because Robinson and Harris made it known that he would not agree to change to another position. At the time, black quarterbacks, even gifted ones such as Marlin Briscoe and Eldridge Dickey, were often involuntarily turned into running backs or wide receivers.

Defying both the late selection and an avalanche of hate mail filled with slurs and threats, Harris beat out six other quarterbacks in training camp. After the rookie threw a touchdown pass in the third preseason game, Buddy Young, the only African American on the NFL’s executive staff, told Harris, “The way you played tonight, you can open up some opportunities.”

Less than a month later, on Sept. 14, 1969, Harris became the first black quarterback to open the NFL season as a starter. His three seasons with the Bills would end up marked by injuries and struggle.

But his career took off when he joined the Los Angeles Rams, guiding them to the NFC championship game in 1974 and 1975. He led the conference in passing efficiency and was chosen most valuable player in the Pro Bowl. His teammates voted him captain. Sport magazine, then the major competitor to Sports Illustrated, put Harris on its cover to mark the tantalizing prospect that the Super Bowl might see its first African American quarterback.

Harris was a hero of the movement for racial justice in the same way Jackie Robinson had been in the early years of his baseball career. He did not need to speak out; his mere presence on the field, as proof of black leadership and black intelligence, inspired black fans to root for Harris’s Rams even against their own home teams. The black public also admired Harris, as it had Robinson decades earlier, for his preternatural dignity under duress and provocation. Under credible death threats, the quarterback sometimes needed security guards to protect him in his hotel room and, once, even during a game itself.

Midway through another solid season in 1976, however, Harris was benched. The official pretext was that he was hobbled by an often-injured knee. The reality was that the Rams’ owner, Carroll Rosenbloom, overruled head coach Chuck Knox in the matter. Not only did Harris lose his starting job, but the Rams spent two years trying to replace him with a procession of four white quarterbacks.

Rosenbloom all but admitted the racial bias in his decision, telling the Los Angeles Times, “Unfortunately, the quarterback position is controversial enough without adding the color element.”

To the contrary, Rosenbloom actually made the Rams quarterback competition into a racial issue. Two journalists — Skip Bayless of the Los Angeles Times (now a Fox Sports personality) and Brad Pye of the Sentinel, the city’s major black newspaper — reported and commented repeatedly on the mistreatment of Harris.

Black members of the Los Angeles City Council also picked up the banner, with council member David Cunningham introducing a resolution assailing the Rams’ front office and most of the white media for their treatment of Harris. The council’s white majority tabled the resolution, which only exacerbated the racial tensions.

At an awards ceremony initially intended to honor Lee Elder, the first African American golfer to play in the Masters, Pye read aloud the council resolution and formally presented it to Harris. As the crowd rose in a standing ovation, Pye added his own postscript: “Harris has demonstrated the kind of courage, as a player and a man, that young men of all races could do well to emulate.” The California State Assembly would later similarly honor Harris.

But in the pre-Internet, pre-cable news, pre-ESPN era, it was the comedian and satirist Richard Pryor who came closest to ingraining the incident in the national consciousness. In a variety-show skit based on the then utterly improbable premise of the United States having a black president, who was holding a news conference, a black journalist from Ebony magazine demanded of Pryor’s chief executive, “I want to know what you gonna do about having more black brothers as quarterbacks in the National Football Honky League.”

The president responded, “I plan not only to have lots of black quarterbacks, but we gonna have black coaches and black owners of teams. As long as there gonna be football, gonna be some black in it somewhere!” Getting ever more worked up, he shouted, “I’m tired of this mess that’s been goin’ down. Ever since the Rams got rid of James Harris, that’s what my job been about.”

By the time Pryor’s show was on the air, the Rams had solved their problem by trading Harris to the San Diego Chargers. As a send-off, the black elite of Los Angeles gathered at the swanky Biltmore Hotel for a farewell party, featuring a red carpet emblazoned with “We Love You Shack.”

Such ardor notwithstanding, Harris spent what should have been the peak years of his career — his late 20s and early 30s — as a backup. He ultimately built a career as an executive for four teams, earning a Super Bowl ring with the 2000 Ravens. As an executive, he saw the fruits of his breakthrough, as African Americans increasingly played quarterback, coached teams and served as general managers.

Kaepernick hopes to go a step further in realizing the dream Pryor outlined, breaching the barrier of team ownership as part of a black investment group trying to buy the Carolina Panthers.

Although Harris never made a physical gesture as indelible and daring as Kaepernick’s bent knee, he was similarly a man who refused to back down and suffered for his ethical backbone. And unlike Kaepernick, he was alone. The black athletes in the NFL during his time did not have the critical mass of activists to overtly support them as they have Kaepernick. Sports journalism in the 1970s largely eschewed coverage of racial and political issues, preferring fawning profiles.

“I had problems I couldn’t discuss with nobody,” Harris told Bayless after being dumped by the Rams. “Others just can’t relate to my problems. I’m a different commodity because of the racial overtones. People can’t relate to your problems until they’ve experienced them, and the things that were happening to me had never happened to anybody before.”

Forty-one years later, despite all the other progress, another black quarterback most assuredly can relate.