It's safe to say that everyone inside the T-Mobile Arena on Sunday (April 2) during the 2017 ACM Awards was going crazy for Florida Georgia Line's incredible performance with the Backstreet Boys. From Carrie Underwood to Keith Urban, several of country music's biggest stars turned into excited fans during the number, but Tim McGraw may have had the best reaction of all.

In a video shared by FGL on Instagram, McGraw is excitedly pointing in amazement as the country stars nail the original moves to BSB's hit "Everybody." Everyone else in the venue was shocked, too, stepping to their feet and dancing right along with the superstar collaborators. The performance kicked off with BSB joining FGL on stage for "God, Your Mama and Me" before launching into one of the '90s pop group's career-defining hits, much to the delight of the crowd.

Tyler Hubbard and Brian Kelley of Florida Georgia Line admit to Entertainment Tonight that they actually learned the choreography the day of the show and that McGraw made a point to let them know how great they did.

"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 says. "I was like, 'I appreciate that, Tim.'"

The performance at the ACM Awards is just one of many times the country act and pop group will take the stage together, as BSB will join Hubbard and Kelley for select dates on their 2017 Smooth Tour. In addition to the show-stopping performance, FGL also took home two ACM awards for Single Record of the Year for "H.O.L.Y" and Vocal Event of the Year with McGraw for their collaboration on "May We All."

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