Matt Damon says Ben Affleck saved him from getting beat up in high school

Matt Damon appeared on the Conan chat show on Monday night where he remembered the last fight he’d been in, and how his longtime friend Ben Affleck came to the rescue. In fact, according to Damon, it was that a day that sparked their decades-long friendship.

As Damon explained, it was a snowy day in the mid ’80s and the neighbourhood kids gathered for a game of snow football. Damon ran his mouth a bit too much to the wrong kid and found himself in a bad situation.

“I mouthed off to this kid that I knew, but he was like your [Conan’s] height, like 6-foot-6, and I might have been 5-3 at the time, and I said something,” Damon said.

Matt Damon and Ben Affleck are seen at the HBO Project Greenlight Filmmaker Showcase on Friday, Nov. 7, 2014 in Hollywood, Calif. (Photo by John Shearer/Invision for HBO/AP Images)

“I’d scored on him or something, and I don’t know, I said something but he came for me. And it was like this mountain of a guy came at me and I was like, ‘Oh man.’ So before I knew it, it was like I was on the ground, he was above me, and I was like, ‘This is gonna be bad.’”

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Lucky for Damon, Affleck had that superhero instinct long before he became Batman.

“It was right then that little 5-foot-2 Ben Affleck tackled this dude off of me, like out of nowhere,” Damon said. “I was, like, a junior and he was, like, a freshman, and he tackled this kid off of me, literally at the risk of his own life.”

LOS ANGELES - MARCH 23: Actor Matt Damon and actor Ben Affleck attend the 70th Annual Academy Awards on March 23, 1998 at Shrine Auditorium in Los Angeles, California. (Photo by Ron Galella, Ltd./Ron Galella Collection via Getty Images)

And that was the moment Damon knew Affleck would be a good friend.

“But I remember that was a big moment,” Damon said, “going like, ‘This guy, he will put himself in a really bad spot for me.’ Like, ‘This is a good friend to have.’”

Matt Damon and Ben Affleck are set to reunite on screen for Sir Ridley Scott’s The Last Duel, which Damon yesterday confirmed goes into production in 2020.

Damon and Affleck are set to star and have also co-written the script with Nicole Holofcener, the Oscar-nominated screenwriter of 2018’s Can You Ever Forgive Me?.

"It's just this really interesting story of perspective, and so Ben and I wrote the male perspectives and Nicole wrote the female perspective and I think it could be really interesting," Damon told ET Online. "So I'm looking forward to making it next year."