Fights have started, and friendships ended, over the question of which actor is the best Batman. However, for Matt Damon -- and, it turns out, his friend Ben Affleck -- the answer is clear. Spoiler alert: It isn't Affleck.

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Appearing Thursday alongside "The LEGO Batman Movie" star Will Arnett on "The Late Show with James Corden," Damon was put on the spot, and asked to name his favorite Batman.

"Well, look, I actually have it on good authority that Will is actually Ben's favorite Batman," Damon replied with a grin. "Absolutely, absolutely. Yeah, yeah, we're all fans of LEGO Batman. I went this last weekend with my kids, and it's just awesome."

However, Affleck remains the one true Batman in the eyes of at least one fan: his 4-year-old son.

"Ben ... he really took the Batman thing pretty seriously, because the 4-year-old thinks he's actually Batman," Damon explained. "But what happened -- this twist that none of us saw coming -- like, that was a really sweet thing, and we're all excited: 'Oh, that's cute, Sam thinks he's Batman.' But then Sam was convinced the FedEx guy was The Joker, because it's the same colors, you know? The green, and the purple. And so, whenever the FedEx guy comes, which is often -- they get packages and scripts and stuff like that -- it's, 'Dad! Dad! Joker here! Joker here!' So Ben is literally on a first-name basis with this guy, because he went out the first day and was like, 'I'll give you 20 bucks if, like, we pretend to fight. My kid thinks you're The Joker.' And so he has to send him away every day: 'Get out of here, Joker!' He does his Batman voice, and his kid thinks he's the greatest thing ever."

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"The LEGO Batman Movie," which topped the North American box office for the second consecutive weekend, has earned $170.8 million worldwide. Directed by Chris McKay, the film also stars Michael Cera as Robin, Zach Galifianakis as Joker, Ralph Fiennes as Alfred Pennyworth, Rosario Dawson as Batgirl, Mariah Carey as Mayor McCasskill, Jenny Slate as Harley Quinn and Billy Dee Williams as Two-Face.

Affleck debuted as the Dark Knight in 2016's "Batman v Superman: Dawn of Justice," and reprised the role in "Suicide Squad." He'll next be seen in the cape and cowl in director Zack Snyder's "Justice League," which also stars Henry Cavill as Superman, Gal Gadot as Wonder Woman, Jason Momoa as Aquaman, Ezra Miller as The Flash and Ray Fisher as Cyborg. The film arrives Nov. 17.

(via Batman-News)