Matt Damon is opening up about his small but memorable contribution to Ben Affleck’s Dunkin’ campaign.

Damon made a surprise appearance alongside Affleck in the campaign’s final installment, which aired during the Super Bowl on Sunday. In it, the “Good Will Hunting” duo join Tom Brady at a recording studio, where they plan to make their musical debut as a pop group dubbed The DunKings.

Among those seemingly underwhelmed by their efforts, however, is Jennifer Lopez, Affleck’s wife and a pop icon. The clip, which also features appearances by rappers Jack Harlow and Fat Joe, ends with Affleck and Damon looking despondent as they exit the studio.

“Remember when I told you I would do anything for you? This is ‘anything,’” Damon quips to Affleck.

Appearing Tuesday on “The Late Show,” Damon explained that the doughnut franchise’s commercial “was not my idea” and noted that the concluding line was, in fact, ad-libbed.

Check out “The DunKings” commercial below:

“I actually said that to him when we were filming,” Damon told host Stephen Colbert. “And he just left it in.”

Later in the interview, Colbert pointed out that Dunkin’ sold the orange and pink tracksuits that the “DunKings” wore in the commercial, prompting him to bring two of the outfits out for him and Damon to wear during their chat.

“By the way, the only qualification for being a DunKing is the willingness to put this on,” Damon quipped. “So you’re in the band. You made it.”

Though Affleck and Damon might have to reconsider the future of their music careers, the campaign itself has won near-unanimous praise from viewers and media outlets. On Monday, Dunkin’ unveiled an extended, four-minute version of the ad.

“The sight of Brady, Affleck, and Damon going full Dunkin’-Boston-nutso-Dunkachino during the Super Bowl? Sorry to RFK Jr., but it made for the best commercial of the night,” Esquire’s Bria McNeal wrote.