Fans who attended Justin Timberlake's concert in Nashville on Friday night (Dec. 19) got more than they bargained for.

Timberlake was performing at the Bridgestone Arena in Music City, and he broke out the acoustic guitar for a cover version of the Garth Brooks classic, 'Friends in Low Places.' Partway through the song, he stopped and said, "Hold on, now something don't feel right, something don't feel right, Nashville."

He then added, "I mean, if you're going to do this -- Garth?"

Brooks then entered the stage to the screams of the fans, picking up the second verse as the packed arena went wild. He also led the crowd in a singalong of the song's "lost" verse, which was not featured on the recording, but he sings at his live shows.

Timberlake has made no secret of his fandom for Brooks. He turned up in the front row at Brooks’ show at the Scottrade Center in St. Louis on Dec. 4, and the following night in Oklahoma City, he covered 'Friends in Low Places' at his own concert.

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