Since appearing on the ABC drama, Nashville, last week, Christina Aguilera has been doing it up country a bit more recently. And she continues on this route when the Back to Basics singer joined Rascal Flatts onstage for an unforgettable duet at the 2015 ACM Awards Sunday night (April 19).

While the other performances were full of energy, the two acts slowed things down starting with "Shotgun," which Christina will be performing on her second episode of Nashville airing on April 22. With only Rascal Flatts' Joe Don Rooney on guitar to accompany her, Christina sings the song effortlessly. And as she gets to the chorus, Gary LeVox from the band joins in. After they sing on the refrain and the song ends, the crowd goes wild.

They then move to another part of the stage where Gary sits at the piano and starts Rascal Flatts' latest single, "Riot." Christina stands at her custom-made red mic stand and waits for her turn on the track. Once the second verse starts, Christina pulls out those whole round notes and puts her Xtina twist on the country tune. The song then takes an even more powerful turn after the guitar solo when a choir comes in and builds up the harmonies established by Christina and Gary.

Although Christina isn't going to drop a country album anytime soon, this collaboration proves her range and shows that crossover duets like this not only work but reach everyone no matter what music they prefer listening to.

See How Pop Stars Looked When They Released Their First Albums