Colin Kaepernick made waves on Jackie Robinson Day in Major League Baseball by comparing himself to the civil rights icon.

The free-agent quarterback known for kneeling during the national anthem tweeted a quote from Robinson’s 1972 biography, “I Never Had It Made,” in which Robinson said that “I cannot stand and sing the anthem. I cannot salute the flag; I know that I am a black man in a white world.”

The post reignited debate over whether Kaepernick deserves to be compared to Robinson, who endured racial taunts and death threats when segregation was still the law in some states by breaking the MLB color barrier in 1947 on his way to a Hall of Fame career.

Kaepernick arrived in the NFL about 65 years too late to break the pro football color barrier, but has been hailed by supporters as a civil rights pioneer for refusing to stand for the anthem before games in a protest against police brutality.

Kaepernick has drawn comparisons to Robinson before. In a November cover story, GQ magazine said his stand “puts him in rare company in sports history: Muhammad Ali, Jackie Robinson — athletes who risked everything to make a difference.”

ESPN’s Stephen A. Smith was having none of it, declaring Monday that, “Kaepernick is not comparable to the great Jackie Robinson.”

He said that if Kaepernick’s intent was to “highlight and illuminate the rationale and the reason behind his protest, I have no problem with that whatsoever,” but slammed any attempt to equate their legacies.

“We’re going to put a stop to all of this stuff for those out there that try to martyr him [Kaepernick] to the point where you think for one second that he needs to be mentioned in the same sentence as Jackie Robinson,” Smith said. “You better pump them damn brakes. I’m not going to tolerate it.”

The former San Francisco 49ers quarterback, who has not played since the 2016 regular season, has filed a grievance against team owners alleging that they have colluded to keep him out of the league over the protests, which have been blamed in part for declining NFL television ratings.

Others argued that Kaepernick was merely pointing out that even a player as revered as Robinson also had a problem with standing for the anthem.

“He’s not invoking Jackie Robinson’s name to say, ‘I am as important as Jackie Robinson,’ ” said Max Kellerman on “First Take.”

Wow! I knew that Jackie Robinson was strong, smart, & righteously angry at racial inequality & injustice (like someone else in this thread), but this quote is stunning. So clear. So direct. So relevant. Thanks Colin. — James J. Zogby (@jjz1600) April 16, 2018

All MLB players wear “42” on April 15, which was declared Jackie Robinson Day in 2004 in honor of the base-stealing Brooklyn Dodgers slugger’s first day in the major leagues. The number has been otherwise retired for all teams.

“Robinson fought against segregation in his sport of the ‘institutionalized’ kind that leftists are so quick to baselessly allege today, whereas Kaepernick has failed to successfully gain employment in a league where plenty of black athletes have become millionaires while still being politically outspoken at least as much as he has,” said a Tuesday post on Medium.

Black players have long dominated the NFL. In 2016, 69.7 percent were black and 27.4 percent were white, according to the Institute for Diversity and Ethics in Sports at the University of Central Florida.