On the second day of the 2016 Southern Ground Music & Food Festival (April 17), Kacey Musgraves played a late-afternoon set before Zac Brown Band closed out the event. Musgraves' time on stage wasn't over at the end of her show, though; during ZBB's set, she reappeared to sing a classic country tune with the band.

The two acts performed Hank Williams' "Hey Good Lookin'" together; "We're gonna do something country!" Musgraves told the audience before Brown and company began strumming the song. Musgraves -- dressed in all back and a white cowboy hat -- took the lead on the first half of the song, before giving ZBB a chance to jam out a bit on the tune.

The audience cheered ZBB and Musgraves' song selection almost as soon as the music started and eagerly sang along to the choruses. Following the musical interlude, Brown offered up vocals on a verse before letting Musgraves finish the song. Press play on the video above to watch the performance.

During their 21-song set on Sunday night, Zac Brown Band also Charlie Daniels Band and more. The night before (April 16), the band offered up re-imagined versions of songs by Queen, the Beatles and Avicii, among others; they even brought the Marshall Tucker Band, also on the bill at Southern Ground 2016, out for a joint cover of the latter’s “Midnight Promises."

“Every night on stage, every time we get together, there’s something new going on … It’s such a thrill that you never know what you’re gonna get when you get up there,” Zac Brown Band fiddler Jimmy De Martini tells The Boot. “It’s definitely a testament to how well these guys can play; everybody in the band is super pro.”

Audiences may not know quite what to expect each night, but they’re in good company.

“I never know what our setlist is until 30 minutes before we go on stage,” ZBB member John Driskell Hopkins tells The Boot. “We roll out there, and there it is.”

The 2016 Southern Ground Music & Food Festival, which took place April 16-17 at Charleston, S.C.’s MUSC Health Stadium, also featured the Tedeschi Trucks Band, Hunter Hayes, Sam Bush, Drake White and the Big Fire and many more. On May 19, Zac Brown Band will begin their 2016 Black Out the Sun Tour.

Photos From the 2016 Southern Ground Music & Food Festival

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