Harrison Ford has become a major fan of baseball pioneer Branch Rickey after researching the late New York Dodgers general manager for a new sports movie.

The veteran actor chose to delve into his real-life character's history after signing on to play Rickey in new movie 42, which chronicles the baseball boss' friendship with the sport's first African-American Major League player and Dodgers legend Jackie Robinson.

Ford tells USA Today newspaper, "The more research I did, the more impressed I was... Anything I could find, I used. I discovered he did things too numerous to count."

He hopes the film, which hits cinemas next year (13), will be more than just a history lesson to moviegoers - but will help recall a time when black men weren't welcome in locker rooms and dug-outs.

He adds, "It's hard to remember the difficulty between the races... Their (Rickey and Robinson) story demonstrates the best of American character."

Meanwhile, Ford admits he turned to British actor Sir Ben Kingsley for advice about how to play a real-life person on film.

The Star Wars star explains, "There are two ways to play (a historical figure). One way is to confine yourself to represent a real person in a narrow vein. The other is to use it as an opportunity. He (Kingsley) said it's an opportunity to use the (real) man as a mask that tells the truth. That's what I wanted to do."

Baseball Hall of Fame member Wesley Branch Rickey is largely credited with breaking Major League Baseball's colour barrier by signing Jackie Robinson, and for drafting the first Hispanic superstar, Roberto Clemente. He also introduced the batting helmet.