On his 2015 Lipstick Graffiti Tour, Sam Hunt began including a medley of '90s hit sung by female acts in his setlist. During a late-night show at the Ryman during CRS 2016, Hunt upped the ante, inviting Charles Kelley to the stage to perform the medley with him.

"One of the things I love about country radio is, you make the listeners and the fans feel like they're part of something, like they're a part of the country music family. And I feel like I've been a part of the country music family since I started listening to country radio 20-something years ago," Hunt told the crowd assembled for his show on Tuesday night (Feb. 9). "Since then, you've turned me on to so many great songs, so many great artists, and now that I'm a little bit more intimately involved in the country music family, I've been able to meet a lot of the cool songwriters and a lot of the great artists behind all that great music ..."

The singer-songwriter then surprised the audience with Kelley; Hunt spent the summer of 2015 opening for Lady Antebellum.

"I don't know what I'm doing here ...," Kelley joked as he walked onstage. "Who's this?"

Hunt and Kelley began the medley with Reba McEntire‘s “Fancy,” followed by Trisha Yearwood‘s “She’s in Love With the Boy” and Mariah Carey‘s “Always Be My Baby," with Kelley mostly providing harmonies (and snapping some selfies with the crowd) to Hunt's lead. The supersized medley also included Cyndi Lauper's "Girls Just Wanna Have Fun," Whitney Houston's "I Wanna Dance With Somebody" and Deana Carter's "Strawberry Wine."

One of the biggest highlights, however, was watching Kelley and guitarist Tyrone Carreker let loose, sing Destiny's Child's "Say My Name" and ad-lib something goofy. Press play on the video above to see the entire performance.

CRS 2016 wraps up on Wednesday (Feb. 10). On Monday (Feb. 15), Hunt is scheduled to perform with Carrie Underwood at the 2016 Grammy Awards.

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