Colin Kaepernick completed 59.2 percent of his passes for 2,241 yards, 16 touchdowns and four interceptions in 2016. He’s unemployed in 2017. (Denis Poroy/Associated Press)

For risking a well-compensated athletic career to pursue social activism, Colin Kaepernick has often been compared with Muhammad Ali. On Sunday, LeBron James mentioned the former boxer while discussing the free agent quarterback, but he also compared Kaepernick to the figure most synonymous with the 20th-century civil rights movement: Martin Luther King Jr.

Speaking to ESPN’s Dave McMenamin after a Cavaliers practice, James said that Kaepernick, who has been unable to sign with a team after parting ways with the 49ers in March, has been “blackballed out of the NFL.” James spoke glowingly of Kaepernick, who began taking a knee during the national anthem to protest racial injustice, specifically police brutality against black men, and who has continued to donate time and money to community-oriented initiatives while waiting for a call from the NFL that seems increasingly unlikely to arrive.

“I’ve commended Kap, and for him to sacrifice everything for the greater good for everyone, for what he truly believed in, the utmost respect to him,” James said. “Obviously he had a vision like Martin Luther King [Jr.], and like some of our all-time greats that people couldn’t see further than what they were doing at the point and time.”

James evoked Ali’s memory in saying, “When it’s something that’s new, and it’s something that people are not educated about or don’t understand what your beliefs are all about, people are so quick to judge and people are so quick to say that what you’re doing is wrong. For [Kaepernick] to sacrifice the sport that he plays, and to sacrifice the things he’s done his whole life because he knew what he believed in, I salute him. I salute and respect that.”

It is not the first time James has praised Kaepernick, but he offered Sunday his strongest and most extensive comments about the quarterback. Last year, while telling reporters that he himself would be standing for the anthem during the upcoming NBA season, James said of the quarterback, “You have the right to voice your opinion, stand for your opinion, and he’s doing it in the most peaceful way I’ve ever seen someone do something.”

“I’m not a politician, but I’ve lived this life and I’ve got a family,” James added at that time, “and what scares me is my kids growing up in this society right now, where innocent lives are being taken and it seems like nothing is being done.”

On Sunday, James pointed out, “all these other quarterbacks out there and players out there that get all these second and third chances that are nowhere near as talented” as Kaepernick. Starting matchups in NFL games that day included Blake Bortles vs. DeShone Kizer, Joe Flacco vs. Brett Hundley, Ryan Fitzpatrick vs. Jay Cutler, Blaine Gabbert vs. Tom Savage and Andy Dalton vs. Brock Osweiler. In another game, rookie Nathan Peterman threw five interceptions in his starting debut before getting benched at halftime.

“I watch football every Sunday, every Thursday, every Monday night. I see all these quarterbacks — first-string, second-team, third-team quarterbacks — that play sometimes when the starter gets hurt or are starters that play. Kap is better than a lot of those guys,” James told ESPN. “Let’s just be honest.”

“It just feels like he’s been blackballed out of the NFL,” James added. “So, I definitely do not respect that. … The only reason I could say he’s not on a team is because the way he took a knee. That’s the only reason.”

Kaepernick was recently compared to King with Pro Football Hall of Famer Shannon Sharpe, now a Fox Sports analyst. “Maybe Colin Kaepernick will never get the respect that he deserves for what he did,” Sharpe said on FS1’s “Undisputed” last week, “but I believe when it’s all said and done, and history is written 30-40 years from now, Colin Kaepernick will be looked upon as some of these mythical figures of the Dr. Kings and Muhammad Alis and the Rosa Parks.”

For his part, King’s oldest son, Martin Luther King III, cited Kaepernick and James as new faces of “black leadership” last year. King said he was “proud” of the athletes’ efforts toward “forms of creative, constructive protest” (via TMZ Sports).

“I mean, [crap], when you’re born black you’re faced with discrimination,” James said Sunday. “It just comes with the territory. So our whole life we’re just trying to figure out ways how we can represent our family, represent us, be as powerful as we can be not only as African American males, but African American women as well.

“That’s why we’re so strong, and that’s why we’re so prideful about what we believe in, because when we’re born, we’re already born behind the eight ball.”

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