Justin Bieber seems a bit more excited than Mark Wahlberg about his stint as a Calvin Klein underwear model.

While on Thursday's Conan, the 45-year-old Patriots Day actor revealed that Bieber had his underwear ads sent over to him. "I was like, 'You don't send a guy pictures like this, in your underwear,'" Wahlberg quipped. "He was proud. It was a big deal for him to do it."

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However, the father of four -- who modeled for Calvin Klein in 1992 -- is at a different stage in his life than the 22-year-old pop star. "I'm trying to move away from that image," he admitted. "People give [Bieber] flack for kind of growing up in the spotlight and they say he has a bit of an attitude, but you look at the look on my face. I mean, I was the biggest punk in the world."

"I can say I've done worse things, but, yeah, that's not one of my proudest moments," he added.

WATCH: Justin Bieber Spoofs His Own Calvin Klein Ads

Wahlberg had nothing but good things to say about Bieber. "He's a very nice young man. He's a friend of mine. I've spent time with him," he insisted. "He's very nice, young and polite compared to what I was."

That being said, during a recent appearance on The Ellen DeGeneres Show, Wahlberg joked that Bieber would have his blessing to date his 13-year-old daughter, Ella, "over my dead body."

Check out what else he had to say about the "Sorry" singer:

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