Oscar-winner Russell Crowe reveals that he kept a promise to Paul Giamatti's dying mom during the production of Cinderella Man. The two starred alongside one another in director Ron Howard's 2005 boxing biopic. Crowe recently revealed that he promised his co-star's mother that her son would be nominated for an Oscar. Amazingly, Crowe was able to keep that promise.

The reveal was made by Russell Crowe in a video breaking down some of the biggest movies in his career. At one point, he revealed that Al Pacino, Crowe's co-star in The Insider, told the studio to "back the kid," meaning Crowe, for an Oscar nomination. This is something he would later say to the brass behind Cinderella Man to help keep the promise made to Paul Giamatti's mom. Here's what Crowe had to say about it.

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"Paul Giamatti's mom died during the course of shooting Cinderella Man, and I made her a promise on the phone that Paul was such an incredible actor, that he would be nominated. And the studio asked me what I wanted to do, and I said, 'Back the kid.' And Paul Giamatti got an Academy Award nomination."

Indeed, Paul Giamatti was one of the five actors nominated in the Best Supporting Actor category at the Academy Awards that year. Giamatti competed against William Hurt (A History of Violence), Jake Gyllenhaal (Brokeback Mountain), Matt Dillon (Crash) and George Clooney (Syriana). Ultimately, it was Clooney who took home the award. Speaking further, Russell Crowe discussed the physical nature of playing boxer James J. Braddock in the movie.

"It was a physically, extremely tough role. I've actually done more difficult physical roles since, but at that time the preparation for that film. If I could show you a list of what we were doing on a daily basis, it was heavy stuff. Ron is a very serious director. He brought Angelo Dundee, who trained 15 world champions, into my life... It required an immense amount of discipline to play that character."

Cinderella Man takes place during the height of the Great Depression and follows ex-boxer James J. Braddock, who has fallen from grace during the economic crisis. He now works as a day laborer until his former manager Joe Gould (Paul Giamatti) offers him an unexpected fight against a rising young contender. What was meant to be a one-time fight turns into a shocking comeback story following a shocking upset. Braddock goes back to fighting full time against the wishes of his wife, Mae. Braddock ultimately gets a shot at fighting the defending champion, Max Baer.

Next up for Russell Crowe, who won an Oscar for his work in Gladiator, is a new thriller called Unhinged. It is expected to be one of the first new movies released once theaters reopen in the U.S. It is currently set for release on August 21. You can check out Crowe's full career retrospective for yourself from the GQ YouTube channel.