The larger-than-life story of baseball great Jackie Robinson will open on the big screen this month along with the beginning of the new baseball season.

“42” is slated to open on April 12, just three days before the 66th anniversary of Robinson’s debut game that broke baseball’s color barrier.

The film follows Robinson, the first African American to play Major League Baseball, as he plays for the Brooklyn Dodgers, and highlights the bond that formed between Robinson and Dodgers general manager and president, Branch Rickey.

Rickey is played by Harrison Ford, who was not originally on the shortlist for the part.

“The filmmakers didn’t send (the script) to me, I just happened upon it,” Ford recently told CNN.

“I came through backdoor channels and I read it and I thought this is a great opportunity to play this character if anybody’s interested in seeing me about it.”

Except no one was. “They would not have known about my ambition to play this kind of character in a faithful way … to approach it as a character actor and be willing and ready to let loose of my former career as a leading man.”

After some persuasion, Ford landed the role of Rickey — although, true to his intent to get lost in the character, you might not even recognize him in the part.

When it came to casting Robinson, writer/director Brian Helgeland, who has previously written screenplays for “Man on Fire” and “A Knight’s Tale,” knew upon meeting Chadwick Boseman that he wanted him to fill the uniform.

The actor, who’s previously appeared on TV in shows like “Lincoln Heights” and “Persons Unknown,” was directing an off-Broadway play at the time of his audition, but just so happened to be in Los Angeles when his agent called about “42.”

But though Helgeland knew right away, “I definitely didn’t know right away,” Boseman told CNN.

After reading for Helgeland the first time, “I came in the next week and read for him again, and realized that he already made his decision and he was trying to prove it to somebody else. I did a baseball tryout, and the rest is history.”

Helgeland “said I was the person who showed the most courage, and that’s why I got it,” Boseman said.

Boseman played some Little League baseball as a kid and describes himself as an athlete. “So it wasn’t like I couldn’t walk and chew gum at the same time,” he joked.

But he obviously needed practice in order to emulate one of the best in the history of baseball.

“We did spring training from the middle of January to May,” he said.

“We prepared as if we were going to play a game.”

In order to see how he was shaping up in his attempt to accurately bring Robinson’s skills to life, Boseman would watch a split-screen of his own practices next to some of Robinson’s Hall of Fame footage — so he could see “how bad I was” compared to Robinson.

Like Boseman, Ford logged hours extensively researching his character, working to understand the ins and outs of the sport, though he’s not a huge sports fan generally.

“I researched the character and the history, and I know the history. I know the circumstances that took place and the character of our nation at the time, but I didn’t know much about the man: Branch Rickey,” Ford said. “There was a lot of research material and I took advantage of all of it, and studied it.”

As for the reason we haven’t seen more Jackie Robinson biopics flood cineplexes, Ford muses that it might be because Robinson’s wife, Rachel, has been careful with her husband’s legacy.

“Until Brian Helgeland produced the script, I don’t think she’d been satisfied with the telling of the story,” Ford said. “And not so much because it glorifies her husband, but because it embraces the fulsome understanding of the circumstances, and so she’s responsible for allowing us to tell the story.”

Topher Gauk-Roger | CNN