Ben Affleck Calls Ex Jennifer Lopez's “Unstoppable ”Performance 'Spectacular': 'Really Proud' of the Film

Ben Affleck and Matt Damon produced Jennifer Lopez's new movie 'Unstoppable' through their production company Artists Equity

Ben Affleck has high praise for ex Jennifer Lopez's work in a new movie he produced.

Affleck, 52, fielded a question about the upcoming wrestling biopic Unstoppable, which stars Lopez, 55, while he, Cillian Murphy and Matt Damon spoke with Entertainment Tonight about a separate movie the group worked on, Small Things Like These.

"Jennifer is spectacular," Affleck said of her performance in the film, while discussing the similarities between Small Things Like These and Unstoppable, which both he and Damon worked on as producers through their production company Artists Equity.

"Unstoppable is a very different movie than this, but in a way it is similarly rooted in the passion of really talented artists, and [director] Billy Goldenberg and Jennifer and Don Cheadle and Jharrel [Jerome] and Bobby Cannavale, all of whom were really passionate about this film," Affleck said, adding that everyone involved got to know the film's subject Anthony Robles and his mom Judy, whom Lopez portrays.

Related: How Ben Affleck Is 'Staying Busy and Happy' amid Jennifer Lopez Divorce (Exclusive Source)

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"It kind of speaks to a certain kind of thing, I guess, we're drawn to, which is we really believe in the power of storytelling when the people involved in it are deeply emotionally connected to the story," Affleck added.

Unstoppable premiered at the Toronto International Film Festival in September, just over two weeks after Lopez filed for divorce from Affleck Aug. 20. Lopez and Damon appeared in Toronto to promote the movie at the festival while Affleck remained in Los Angeles.

Related: Ben Affleck Spotted on Set of New Movie as His Divorce from Jennifer Lopez Continues to Be Finalized 

Small Things Like These, meanwhile, is adapted from the 2022 novel by Claire Keegan and features Oscar-winner Murphy, 48, as both star and producer.

Unstoppable follows the real-life story of Robles, 36, a wrestler born with one leg who won an NCAA individual national championship in 2011. The movie is adapted by screenwriters Eric Champnella, Alex Harris and John Hindman from Robles' 2012 memoir Unstoppable: From Underdog to Undefeated: How I Became a Champion.

"It's another one we're really, really proud of, and I think if there's any sort of key to what success we've had so far and I feel already even though Small Things Like These hasn't opened yet, it's just an enormous success for us because of how beautiful it is," Affleck told ET. "We believed in the right people, and Unstoppable is another example of it."

Unstoppable is in theaters Dec. 6; Small Things Like These is out Nov. 8.