Florida Georgia Line might have a little more boy band in them than anyone realized!
ET's Nancy O'Dell caught up with Tyler Hubbard and Brian Kelley backstage after their epic performance with the Backstreet Boys at the ACM Awards in Las Vegas on Sunday, where they revealed that they only learned the boy band's choreography hours before taking the stage.
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"I still have the counts and steps in my head of that dance. We learned it last night, it was a last minute... [we learned it] today actually," Hubbard confessed. "I'm not going to lie."
"[The Backstreet Boys are] now a seven-man band, actually," Kelley joked.
Florida Georgia Line performed a number of songs during their performance with the boy band, including their duet, "God, Your Mama and Me," but it was Hubbard and Kelley's ability to pick up the choreography during the Backstreet Boys' "Everybody," that really got the crowd riled up -- Tim McGraw especially.
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"Somebody just showed us a clip and we actually were just hanging with him. We saw the video and he's pointing. He goes, 'I was pointing at you 'cause you were nailing all the moves, you got ‘em!'" Hubbard recalled. "I was like, 'I appreciate that, Tim.'"
McGraw wasn't the only one jamming out in the crowd, though. Nicole Kidman, Keith Urban, Faith Hill and Carrie Underwood all went wild for the performance.
"I didn’t really see them at the moment we were dancing, but I saw everybody having a good time and that’s the moment we've been waiting for all day. It's kind of nice it's over, but at the same time, that was a blast," Kelley said. "That was so much fun and the Backstreet Boys are amazing. They’re great teachers as well, seriously."
"They got timeless hits. They’re staying creative, they’re staying busy, they’re staying fresh and they got great attitudes, positive energy and they’re like brothers," Hubbard added. "We've really created a cool bond and almost mentorship at times too, you know? It's really special. We've shared some success thus far, but I think the friendship more than anything means a lot to us, it really does."
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ET caught up with the Backstreet Boys in February, where they revealed the secret to their decades-long career and friendship. See more in the video below.