This story was excerpted from John Denton's Cardinals Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

Jackie Robinson’s ability and willingness to endure racial taunts and off-field injustices to break baseball’s color barrier will always be considered as one of the landmark moments in sports history.

However, the most impactful aspect of Robinson’s legacy lies in the opportunities that his sacrifices created for others who followed him in baseball. Other Black star players, such as Bob Gibson, Bill White, Curt Flood, Don Newcombe and others, would go on to benefit from the proverbial doors opened by Robinson. Robinson’s impact even stretched beyond the foul poles, where people of color -- such as longtime KMOX broadcaster and Cardinals Radio Network reporter Mike Claiborne -- got opportunities to work in and around baseball because of Robinson’s insistence on pushing for change.

“Whenever I started out in this business, other people didn’t look like me, and because of Jackie, I got a chance,” said Claiborne, who started at St. Louis’ famed KMOX in 1981 and conducted a postgame radio show with Gibson from 1983-89. “Because of Bill White -- who I think is the most influential African American athlete after Jackie Robinson -- I got a chance. So, I owe a lot of the opportunities I got to guys like Jackie and Bill White.”

As Gibson, White, Claiborne and others can attest, opportunities were more prevalent following Robinson’s efforts to shatter baseball’s color barrier, but that didn’t mean things were easy for those professionals while working in baseball. In the History Channel documentary “After Jackie,” which debuts Sunday at 8 p.m. ET/7 p.m. CT, director Andre Gaines explores the struggles for racial equality that Black players in baseball had to endure long after Robinson’s breakthrough on April 15, 1947.

The two-hour documentary has a major Cardinals influence, as former Redbirds Gibson, White, and Flood -- and even St. Louis’ Claiborne -- are featured prominently throughout while discussing the fight against segregation, racial discrimination and standing up for the rights of Black people everywhere.

Gibson, a Hall of Famer widely considered to be the greatest pitcher in Cardinals history, often told stories of the difficulties he and other Black players endured in the years following Robinson breaking the color barrier, Claiborne said. Those were anything but easy times to endure -- even for a talent such as Gibson.

“Bob Gibson was as good a friend as I’ve ever had in my life,” Claiborne confided. “Bob was a guy people were scared of because he had that tough demeanor, but he would get hateful letters and he dealt with a lot of racial stuff. The things that really riled him up most were having to stay in different hotels and eat in different restaurants [than his Cardinals teammates]. That really disappointed him. He had grown up in a tough part of Omaha, Neb., and he always said, ‘It’s one thing if you’ve grown up in an area and they have disdain for you, but for [baseball fans] to throw stuff at you and yell things and not even know you' -- that was something he could never understand.

“Gibby was a baseball pitcher who just so happened to be Black,” Claiborne continued. “The stuff he had to endure, he was bitter about it. There was one guy in the [Cardinals'] organization who would always tell him, ‘You should go play basketball.’ This one guy put Bob in the bullpen and told him, ‘You’ll never make it here; you should think about playing basketball.’ He never had a liking for that guy, and he was always upset about that.”

Gibson would go on to win 251 games, two World Series, the 1968 MVP and two Cy Young Awards while in a Cardinals uniform. In “After Jackie," Gibson details the pain caused by some MLB executives and fans feeling as though Black players didn’t have the aptitude to be pitchers. Ultimately, Gibson took the opportunities made available to him by Robinson’s courage and showed plenty of grit himself in becoming one of the most dominant pitchers in MLB history.