Justin Bieber Sent Mark Wahlberg His Underwear Ads; Mark Wahlberg Wasn't Delighted

Casting a major actor or pop star in an fashion campaign is completely mainstream now – in fact, the stars are not only starring in the ads, but designing the clothes themselves. But back in the '90s, it was slightly more groundbreaking stuff. And one of the faces that helped transition us into the modern era of celebrity spokesmanship was indisputably Mark Wahlberg as the snarling, shirtless visage of Calvin Klein underwear. But while that mantle may have now been taken from his shoulders thanks to Justin Bieber's turn in his tighty whities, it seems the pop star is still seeking out the OG underwear model's approval, sending the actor a few of his campaign images – to Wahlberg's surprise.

During Wahlberg's recent appearance on Conan, O'Brien opens up the segment with a a side-by-side comparison of the two campaigns inspiring a round of dog whistles and whooping from the audience. "How do you feel about Justin Bieber doing it, did he reach out to you in any way?" O'Brien asks.

Walberg responds, "Actually, you know what, he is a very nice young man, he's a friend of mine, I've spent time with him. He did send me the pictures and I was like, 'You don't send a guy pictures like this in your underwear.'"

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O'Brien is incredulous, so Wahlberg explains: "He was proud, you know, it was a big deal for him to do. And I was like, I am at 45, a dad and a husband, a father of four, I'm trying to move away from that image. But, you know what? People give him flack for growing up in the spotlight and they say he has a bit of an attitude, but look at the look on my face, I mean, I was the biggest punk in the world. He's very nice and young and polite in comparison to what I was."

Then, pointing out what we've all thought for years, O'Brien suggests, "You look like you're just causing yourself pain by squeezing yourself. That is the face you make when you squeeze your sack." Wahlberg concluded, "Well, I can't say I [haven't] done worse things, but yeah, that wasn't one of my proudest moments." And yet, it's a moment that will still live on forever in fashion history, just like Bieber's.

What do you think of Mark Wahlberg's story? Who would you like to see take over the Calvin Klein role next? Sound off below!