Avril Lavigne busts a move on a bar in Mexico.

Here we thought Rihanna was the gonna be the indisputable winner of our (highly) unofficial "Which Celebrity's Having The Best Summer" contest. But NOPE. Avril Lavigne's in the running after seeing these recent photos of her dancing on a bar on vacation in Los Cabos, Mexico. Annnd it's official: Dance on a bar = winning by a landslide! (And, yes, it's in our job description to referee these types of serious competitions.)

Check out more photos of Avril Lavigne party-rocking in Mexico after the jump!

Avril and her friend pretend they're a human shower.

The "What The Hell" singer was snapped showing off her best "Coyote Ugly" impression while enjoying adult refreshments and whooping it up with friends on the beach. And while we're kinda sad we haven't heard any new tunes from Avril in a while, we're just glad to see that she's isn't wasting her summer catching up on reruns of "House Hunters" and instead attends plush private parties in glamorous tropical locations with her BFFs.

Avril's just squashing a bug on that landed on her friend's chest... yeah, that's it.

But, wait. How do we know these are Avril's besties and not some total randos she met doing karaoke at the hotel bar the night before? Well, we don't. But judging by this photo of Avril offering a lady friend what looks to be a free breast exam, we have to assume they have some sort of special bond (and it's most likely called "tequila").

Photo credit: Splash News