Excuse You, Selena Gomez???

What in the world is this all about?

For some reason we cannot fathom, Selena Gomez decided to pull out a Backstreet Boy cover at her gig in San Diego this weekend.

The poor thing had to sing it well below her register (or maybe she can’t sing well?), so she sounds like she smoked a pack of cigarettes before going on. And she couldn’t even sing most of it! Some dude named Greg had to jump in!

Whose idea was this???

Watch her rendition above!