Ben Affleck Teases Matt Damon With Epic Throwback Pics in Honor of #OldHeadshotDay

Ben Affleck made sure that Matt Damon took part in Old Headshot Day, whether his pal liked it or not.

Though the hashtag was trending on social media on Friday, Affleck took to Instagram on Saturday with a trio of throwbacks -- just not of himself.

The Justice Leaguestar shared some epic black-and-white pics of Damon that look to be from the '90s, which is when the Massachusetts natives were first starting to make their names in Hollywood. (You remember that little movie the two worked on together called Good Will Hunting, don't you?) There's even a shirtless snap in the bunch, where Damon is crossing his hands over his chest as he stares sultrily into the camera.

"I know this is a day late, but Matt isn't on Instagram so thought I'd help him out. #OldHeadshotDay," Affleck captioned the headshots.

The 45-year-old actor is all about lovingly roasting his longtime friend these days. Just last week, he took to Twitter to tell Chris Hemsworth that he could have Damon as a pal after a report surfaced saying that Damon, 47, was distancing himself from Affleck and growing closer to Hemsworth. "I'm Team @JimmyKimmel anyways," Affleck jokingly responded to the rumors.

Though Affleck didn't share any epic old photos of his own in honor of Old Headshot Day, his ex, Jennifer Garner, sure did.

"Why so serious, twenty two year old Jen? #oldheadshotday. #1994," the Alias alum -- who shares three kids, daughters Seraphina and Violet and son Samuel with Affleck -- captioned the black-and-white image on Instagram.

Tons of other celebs also gamely took part in the throwback phenomenon. Kristen Bell also didn't share hers to Instagram until Saturday, writing, "Better late than never. Swipe left for my attempt at side ponies, attitude, and a bit of croquet."

Melissa McCarthy gifted us with two of her amazing first headshots.

And while plenty of people joked that it looked like they were auditioning for Buffy the Vampire Slayer in their early headshots, Sarah Michelle Gellar -- aka Buffy herself -- shared one of her own.

Check out even more amazing flashbacks from the other stars who took part in Old Headshot Day, including plenty of cast members from '90s faves like One Tree Hill and Dawson's Creek: