Justin Timberlake mocks Justin Bieber in unaired "SNL" sketch

Justin Timberlake and Andy Samberg in an unaired "Saturday Night Live" sketch.

(CBS) When Justin Timberlake hosted "Saturday Night Live" last weekend, we saw him profess (in song) that he wasn't going to sing and consider the merits of a three-way with Lady Gaga and Andy Samberg.

What we didn't get to see was Timberlake, dressed as Mozart, making fun of Justin Bieber. But, now we can.

Pictures: Justin Timberlake
Pictures: Justin Bieber

An "SNL" sketch from rehearsals shows the actor-turned-singer taking aim at the teen heartthrob. Though the skit didn't make it to air, it's now getting laughs online.

In the sketch, he jokes about his transition from singing to an acting career and laments the lack of accolades for his role in "The Social Network."

When his friends threaten to start hanging out with Bieber instead, he exclaims, "Bieber?! Come on, you can't be serious. Why don't you put a wig on a chipmunk and tell it to act like a black man!"

So far, Bieber hasn't responded.

Tell us: What did you think of the sketch?