Halsey knows that when in Nashville, you should do as the Nashvillians do: sing karaoke. The singer-songwriter had a concert in Music City on Wednesday (July 18), and after the show hit up a local joint for what became a second concert co-starring Kelsea Ballerini.

And yes, it was epic. The two took the makeshift stage in a corner of the iconic Santa's Pub bar to do a singalong of Fleetwood Mac's "Landslide," which was caught on video by another country singer, Kalie Shorr.

Then, it was apparently time for Kid Rock and Sheryl Crow's classic duet, "Picture."

"I PUT YOUR PICTURE AWAY! SAT DOWN AND CRIED TODAY!" Halsey writes on social media alongside a picture of her and Ballerini jammimg. "Heartbreak karaoke and too many beers with the realest one of them all."

It's not clear if other Santa's Pub patrons knew what a treat they were getting.

Ballerini attended Halsey's Nashville tour stop and seemed to be prepped for a good night before the show even began, sharing with her fans that, "if you hear someone screaming castle uncontrollably, it’s 100% me."

The karaoke session was a mighty nice break for Ballerini, who has had quite a busy summer thus far. Not only has she been out on the road with Keith Urban, but she will also co-host a three-hour CMA Fest Special on ABC alongside Thomas Rhett on August 8.

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