Foremost among these gentlemen: the incomparable Roy Campanella.
A biracial catcher blessed with remarkable power and character to match, Campy showed beyond reasonable doubt in 1948 that African-Americans were more than equal to the task of handling the multiple requirements associated with managing a big league pitching staff.
Campanella, a Philadelphian born and bred, was 26, with considerable experience in the Negro Leagues when he made his Major League debut that year.
He went on to collect three National League Most Valuable Player awards (1951, '53 and '55) and make eight All-Star teams. In '53, his best season, he hit .312 with 41 homers and a league-best 142 RBIs. His career on-base-plus-slugging: .860.
Yet, oddly, Campanella's Hall of Fame election didn't occur until 1969, 12 years after an auto accident left him paralyzed and bound to a wheelchair until his passing in 1993. He'd come up short six times. Voters apparently were hard to impress in those days.
If he seemed always consigned to sidebar story status, overshadowed by Robinson's impact, Campanella's historical achievement was significant.
He systematically and emphatically shot down stereotypes involving aptitude, attitude, adaptability and leadership at the position that is baseball's answer to quarterback.
Doing it with grace and an endearing smile, Campy -- just as Jackie had -- paved the way for all those who would follow. Prominent among those was Elston Howard, the Yankees' first African-American position player of impact.
"It gets totally overlooked now, his importance," former pitcher Al Downing said on the phone from his home in Southern California. "But Roy went through all those same trials and tribulations as Jackie. It was a tremendous challenge he faced, knowing it would set black catchers back if he didn't succeed.
"Not only did he have to handle a position where you command the whole field; he had to win over a veteran pitching staff when he took [over] the catching job. Knowing Roy, the outgoing personality he had, those guys couldn't help but grow to like him -- and respect him."
Downing, who signed and debuted with the Yankees in 1961 at 20, was 72-57 with a 3.23 ERA as the first successful African-American pitcher in franchise history.
He moved on to Oakland and Milwaukee before being dealt to the Dodgers in 1971, winning 20 games. That was when he got to know Campanella, a fixture around Dodger Stadium and Dodgertown in Vero Beach, Fla., during Spring Training.
"Players know who can play," Downing said. "I don't think that was ever the issue with the early black players. It was more a matter of the media and fans, how they would take it. They could be rough -- believe me.
"But you have to remember that those guys who came first -- Jackie, Roy, Don Newcombe, Ellie [Howard] -- they weren't kids. They'd already played a lot of baseball and been exposed to a lot of things. Those were tough guys, mentally and physically. They had to be."
Downing, best known for delivering home run No. 715 to Henry Aaron in 1974, threw pure heat when he arrived as a force in the Bronx in '63, going 13-5 with a 2.56 ERA. He would lead the American League in strikeouts the following season with 217 in 244 innings, going 13-8.
A serious arm injury forced him to alter his style, but Downing adjusted. In '71, his best season, he had five shutouts and unleashed a career-high 262 1/3 innings while winning 20 games. He ended his career with the Dodgers in '77.
Growing up in Trenton, N.J., Downing was keenly aware of the Negro Leagues and their buses full of vibrant, fun-loving stars. With the Yankees, "Ace," as he would come to be known to teammates, developed a highly productive rapport with Howard, the 1963 AL MVP.
"The Yankees converted him into a catcher when they saw Yogi [Berra] was nearing the end of the road," Downing said. "Ellie had been an outfielder-first baseman for the [Kansas City] Monarchs and when he came up to the Yankees [in 1955].
"The Yankees always had a lot of good catchers in their system, but they saw Ellie's potential and decided to hedge their bets against the future and make him a catcher."
Howard's first mentor was Bill Dickey, the legendary Yankees receiver.
"I remember Ellie telling me he couldn't believe how nice a guy Bill Dickey was," Downing said. "Ellie had another great teacher later in Jim Hegan, who'd been one of the best catchers in the game for the Indians.
"Ellie was determined to stay in the big leagues. He was a very good student, and he became a great catcher. Not many people seem to realize how important a catcher is to a pitching staff. Maybe you have to be a pitcher to fully understand.
"To me, Ellie and Jim Gilliam are the most underrated players of all time."
Howard and Gilliam had something else in common. They died much too young: Howard at 51, Gilliam at 49.
Campanella made it to 71. He liked to park himself in the right-field corner at Holman Stadium in Dodgertown, sharing stories and insights with a wide-eyed kid reporter who understood fully how incredibly lucky he was.
"Don't take life for granted," Campy would say, soaking up some sun while observing the game he loved. "Enjoy every day, young man."