52nd ACM Awards: The night's standout performances Florida Georgia Line and The Backstreet Boys joined forces to steal the show.

 -- While trophies were presented at last night's 52nd ACM Awards, the three-hour show also packed in performances from more than 25 different acts, many of whom were performing brand-new singles. Here's a look at who sang what:

-- Entertainer of the year winner Jason Aldean opened the show as part of a medley that featured all the nominees in that category singing their big hits: After he kicked things off with "Lights Come On," he was followed by Luke Bryan with "Move," Florida Georgia Line with "H.O.L.Y.," Carrie Underwood with "Church Bells" and Keith Urban with "Wasted Time."

-- Co-hosts Luke Bryan and Dierks Bentley teamed with Eagles guitarist Joe Walsh to pay tribute to the late Chuck Berry with "Johnny B. Goode."

-- Sam Hunt performed "Body Like a Back Road," which he sang partly from the audience, sitting with his arm around his significant other Hannah Lee Fowler.

-- Dierks Bentley performed "Black," and later returned to team up with Cole Swindell for a duet on "Flatliner."

-- New female vocalist of the year winner Maren Morris sang "I Could Use a Love Song," and later returned to team up with male vocalist and song of the year winner Thomas Rhett for their new duet, "Cravin' You."

-- Jason Aldean sang "Any Ol' Barstool."

-- Female vocalist and album of the year winner Miranda Lambert sang a simple, solo, stripped-down version of "Tin Man."

-- Rascal Flatts sang their new single "Yours If You Want It"

-- Keith Urban sang "Blue Ain't Your Color", which was shot in black and white, except for his blue guitar and blue background. Then Carrie Underwood joined him for their duet "The Fighter" while the dancers from the video performed in the background.

-- Vocal group winners Little Big Town sang their new single "Happy People" in front of a video screen showing wildly colored flowers blooming.

-- Lady Antebellum delivered their funky new single "You Look Good" joined by a massive horn section; Charles Kelley threw a bit of Bill Withers' "Use Me" into the middle of the song. It was so well-received that when Little Big Town won, they came on stage and said they just wanted to be part of Lady A's band.

-- Vocal duo and new vocal duo or group winners Brothers Osborne sang "It Ain't My Fault." New male vocalist winner Jon Pardi sang "Dirt on My Boots."

-- Wearing a tiny pink sequinned bodysuit, Kelsea Ballerina sang "Yeah Boy"

-- Chris Stapleton debuted a rockin' new song called "Second One to Know"

-- Brett Eldredge performed "Something I'm Good At" while walking from an upstairs lounge down through the aisles, while interacting with the performers from the Las Vegas adult cabaret show Absinthe.

-- Luke Bryan sang "Fast" while standing in what looked like a mirrored box with dozens and dozens of light bulbs hanging around him.

-- Tim McGraw and Faith Hill delivered their new duet "Speak to a Girl," looking and sounding as great as ever. They started off singing on two separate stages and then walked towards each other -- at the end, Hill jumped up and down in delight, they embraced, and McGraw lifted her off the floor.

-- Old Dominion sang their new single "No Such Thing as a Broken Heart."

-- Reba McEntire teamed with Christian music star Lauren Daigle to sing the spiritual hit "Back to God."

-- Florida Georgia Line and The Backstreet Boys joined forces for their duet "God, Your Mama and Me," and then, to the audience's delight, blew the roof off the T-Mobile Arena by singing "Everybody (Backstreet's Back)," complete with the song's original choreography. Carrie Underwood, Keith Urban and Tim McGraw were some of the many stars singing along to every word.