Watch Justin Timberlake Surprise Crowd with 'Friends in Low Places,' Featuring Garth Brooks

"Something don't feel right," he said before welcoming the legend onstage.

— -- It was the surprise of a lifetime.

In the video, posted in its entirety on YouTube, Timberlake, 33, starts singing the song first, the crowd joins in next, then Brooks takes the stage and the crowd goes nuts.

"Hold on," Timberlake says after the second verse, before welcoming the legend onstage. "Something don't feel right."