While you were joke-posting pictures of a burrito, Beyoncé or both for #NationalBestFriendDay, Batfleck took the sentimental route by commemorating his most successful lifelong relationship with Jason Bourne.
On Wednesday, Affleck shared a throwback photo collage of a birthday celebration for Damon that, of course, ended with Affleck's face covered in cake.
"This guy. #NationalBestFriendsDay," the "Batman v Superman" actor captioned the photo.
It has been quite a week for the lovebirds as they accepted the Guys of the Decade award on Saturday at Spike’s Guys Choice Awards, which is inexplicably still a thing. In their acceptance speech, Affleck poked fun at some of the duo's more controversial roles, acknowledging that each of their careers faced ups and downs.
"I think it goes without saying that this is an award Matt and I have been dreaming about since we were little boys," Affleck told the crowd during their acceptance speech. "I did 'Gigli,' and Matt did that Liberace movie and all of a sudden, it all seemed out of reach. Then I did ['Batman v Superman'] and all of a sudden, it was back in reach again."
Um, that Liberace movie -- "Behind the Candelabra" -- was magnificent and should never be mentioned in the same sentence as "Gigli." So, bye.
Affleck has apparently been in a nostalgic mood as of late, sharing a photo of himself serving hot college librarian vibes from 1998.
Ah, better times.