A version of this story originally ran in January 2021.

Jackie Robinson integrated the National League in April 1947. Larry Doby integrated the American League three months later. As monumental and consequential as those debuts were, segregation remained a reality in professional baseball -- and American life, in general -- for many years afterward.

That reality was particularly pronounced in the Deep South, where Jim Crow laws still ruled the land and racial tensions were deeply rooted. And the South Atlantic League (or “Sally League”), which had teams in such segregation strongholds as Knoxville, Tenn.; and Savannah, Macon, Columbus and Augusta, Ga.; posed a deep challenge for integration efforts.

This is the challenge that 19-year-old second baseman Hank Aaron and two fellow players in the Braves’ Minor League system -- shortstop Felix Mantilla and outfielder Horace Garner -- faced in 1953, when they were assigned to the franchise’s Class A affiliate in Jacksonville, Fla. Along with two players from the Athletics’ Savannah squad -- Buddy Reedy and Al Isreal -- they broke the color barrier in the most notorious of the white Minor Leagues.

It is an important, often ignored piece of the late Aaron’s enormous legacy.

“Henry would have a more difficult time even than Robinson,” author Howard Bryant argued in “The Last Hero,” his biography of Aaron. “Where Robinson would have the benefit of going to his home ballpark in Brooklyn half the time, the Sally League would play all of its games in the Deep South. Even the home park, Jacksonville, would not always be a friendly place.

“Henry knew he might be able to win over the home fans with spirited play, but off the field, he found that Jacksonville was another southern town that was not ready to treat him with any degree of humanity.”

Jacksonville’s team, previously known as the Tars, was newly affiliated with the Braves and took on the nickname of the Major League club, which itself was new to Milwaukee that season. So integration was part of an overall change taking place.

From what we know of Aaron’s 1952 season, in Eau Claire, Wis., his .336 batting average was probably worthy of a bigger promotion than the one that sent him to Jacksonville. (Interestingly, the Braves’ Double-A team at that time was in Atlanta, where Aaron would, of course, go on to have his seminal baseball moment.) But the club opted to bring him along slowly, and the South Atlantic League would test him in ways that had nothing to do with baseball.

Having grown up in Mobile, Ala., Aaron was all too familiar with what it meant to have dark skin in the Deep South. But for Mantilla, a Puerto Rico native of Afro-Puerto Rican descent, segregation laws and the language barrier were new phenomena. He and Aaron formed a friendship, and Aaron was instrumental in helping Mantilla adapt to the difficulties.

“It was Hank who always kept me away from the things that could have gotten me in trouble,” Mantilla told Bryant. “Hank and I relied on each other. We tried not to let the other out of our sight.”

By law, the three Black players were not permitted to live with their white teammates. And so they were taken in by local business owner Manuel Rivera, who, like Mantilla, was of Afro-Puerto Rican descent. Some of their white teammates put themselves in danger by going out to dinner with them, sometimes with a baseball bat to scare off any aggressors.

The field was a more comfortable place, but no sanctuary. Some “fans” would jeer Jacksonville’s black-skinned players and call them “alligator bait.”

“They wouldn’t boo you because you were playing bad,” Mantilla told Sport Magazine in 1965. “It was just because you were colored.”

• Aaron was a beacon of unmatched grace

Aaron, Mantilla and Garner were taught to ignore the vitriol, to shrug off unjust umpiring, to put their heads down and play. It was the code that Robinson and Doby and all of baseball’s Black pioneers were forced to follow.

One day, however, Mantilla could not bring himself to abide by those terms. The Black players were thrown high and tight pitches as a matter of routine, yet a particular head-hunter of a pitcher named John Waselchuk -- in a close game on an already heated July day in which fans were jawing at each other in the segregated stands and police had arrived at the scene -- set Mantilla off. Mantilla began to charge the mound and, had Garner not interjected and dragged his teammate to the ground, the situation may have gotten out of control.

Race-related difficulty and discord did not stop Jacksonville, which until then had been a perennial basement dweller, from storming up the Sally standings. The Braves finished first, with a 93-44 record, and Aaron led the league with a .362 batting average and 36 doubles while ranking second with 22 home runs. He was named the South Atlantic League’s MVP, and he and Mantilla were both All-Stars.

And that 1953 season was consequential off the field for Aaron, as well. Early in the year, he met his first wife, Barbara Lucas, a Jacksonville native and student at a local business school. The two married later that year. (They divorced in 1971.)

The more they won baseball games, the more Aaron, Mantilla and Garner won over the Jacksonville fans, but only to a point. Mantilla told Bryant of a game in which he and Aaron had played particularly well in a hard-fought victory and a white fan approached them afterward to congratulate them. But even then, the man referred to them by a racial slur.

So Jacksonville gave Aaron a taste of what he would endure in his Major League career, when the Braves moved from Milwaukee to Atlanta and, particularly, when he neared Babe Ruth’s career home run record and began to receive an onslaught of hate mail and death threats.

Playing in Old Dixie meant that Aaron could not be just another ballplayer. Prejudice was a part of his life and is a part of his story. And while it is Aaron’s graceful handling of the ugliness he endured during the Ruth pursuit that earns him status as a Civil Rights icon, Jacksonville is a part of the story that should not be ignored. For much like Robinson and Doby, Aaron experienced and understood the great difficulty of crossing a baseball color barrier.