Britney Spears Lip Syncs to Sia's Vocals During "Perfume" & We Hope It Doesn't Bring Down Her Reputation — VIDEO

Performing in Vegas for an extended period of time must have really rubbed off on Britney Spears because apparently, she's taken to doing celebrity impersonations. That's completely fine when performing karaoke or singing in the shower, but not during a concert for fans who paid to see her perform. During one of the singer's recent "Piece of Me" shows at Planet Hollywood, Spears lip-synced "Perfume," and while the song may sound like classic Britney Spears, the vocals the audience heard were Sia's, the writer who penned the song. Yikes.

If this is how Spears intends to "Work, Bitch," then she may want to rethink her strategy. There's no denying that Sia's an awesome songwriter and singer who's written chart-topping hits for everyone, including Beyoncé, Katy Perry and Christina Aguilera, so I can't blame Spears for trying to mimic Sia, kind of like Rihanna did with "Diamonds." Though the cat has long escaped the bag when it comes to Spears' notorious lip-syncing, fake-singing along to another artist's vocals during a performance is just . . . bad.

Aside from the fact that the sheer carelessness of this mistake makes it super embarrassing, it's also disappointing because Spears has been doing really well lately. For quite some time now, her name hasn't been sullied by any outlandish scandals or negative gossip about her personal life. She started this year out on a good note by winning a People's Choice Award for "Favorite Pop Artist," she's in the midst of her Las Vegas residency (where this awful performance faux pas was committed), is enjoying her time as a mother of two boys, plus she recently announced plans for her own line of lingerie. So basically, things are looking up for Spears. But still, this incident is one major fail that could swiftly bring her reputation tumbling back down.

Listen to the clip below: