Saturday Night Live veteran Bill Hader appeared on Watch What Happens Live with Andy Cohen Thursday night (March 22), where he was asked by a caller who the worst musical guest on the NBC show ever was. His answer? Perhaps unsurprisingly, Justin Bieber.

"It was Bieber. Bieber, he just was in a bad place," Hader admitted, explaining, "Maybe he’s in a better place [now], but back then it was rough."

"He was just so huge," he added. "Everyone’s usually on great behavior. Everyone’s very excited and great behavior most [of the] time, 100 percent. Bieber’s the only one in my experience. I think it was just...he seemed exhausted or at the end of a rope.”

Watch the interview, below:

In February 2013, Bieber appeared on SNL as both the host and musical guest. He had just released his hit album, Believe, and was in the midst of a world tour. However, 2013 was a particularly difficult year for Bieber, who constantly found himself in the middle of tabloid controversy after a number of incidents, including the time he rudely urinated in a bucket in a restaurant.

Bieber has been a hot topic on SNL over the years, being portrayed in various skits by cast members and guests alike, including Miley Cyrus, Jimmy Fallon and Kate McKinnon.

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