This is not something we thought we'd ever witness... Justin Timberlake played Nashville's Bridgestone Arena on Friday night and decided he would pay homage to a country music legend and performed a cover of Garth Brooks' 'Friends In Low Places'. The 33-year-old halted the performance after the first verse, telling the crowd: "Hold on, now something don't feel right, something don't feel right, Nashville." "I mean if you're going to do this," he continued. It was then Brooks made his surprise appearance and the crowd went absolutely wild. 52-year-old Brooks decided he would capture the moment onstage and shot a short clip of the pair singing, which he uploaded to his Instagram with the caption: "I saw an ENTERTAINER tonight! @justintimberlake #Justinrcredible [sic]"

A video posted by Garth Brooks (@garthbrooks) on Dec 12, 2014 at 10:33pm PST

It appears Justin TImberlake is as big a Garth Brooks fan as the thousands of Irish that camped out to secure tickets for the Croke Park gigs that didn't go ahead... Is that wound still a little to fresh to bring up that subject?  Timberlake reposted the same video to his own Instagram, with the caption: "Whoa. Whoa. Whoa. So... Yes. This happened".  Followed by a shot of the pair on stage.  "Last one... Just two boys admiring a sold-out crowd in Nashville."

A photo posted by Justin Timberlake (@justintimberlake) on Dec 12, 2014 at 11:45pm PST

A fan captured the moment on camera, you can watch it in full here: https://www.youtube.com/watch?v=nxW3ZKc-jdE Video via YouTube/Alex McDaniel