Kenny Chesney made a surprise appearance during Grace Potter & the Nocturnals' Saturday night (Oct. 30) performance at Nashville's Ryman Auditorium. Potter, lead vocalist for the Vermont-based rock band, provides vocals on "You and Tequila," a track on Chesney's latest album, Hemingway's Whiskey. In introducing the song near the end of her band's opening set for the Avett Brothers, Potter told the crowd, "This one doesn't belong to us. It belongs to a good friend of ours. We're also gonna borrow a good friend tonight. Ladies and gentlemen, Mr. Kenny Chesney." While many in the audience seemed to be in a state of disbelief, Chesney received a warm welcome when he walked onstage wearing khaki pants, blue long-sleeve T-shirt and knit cap. He watched the band's entire set from the side of the stage. The Avett Brothers headlined sold-out shows at the Ryman on Friday and Saturday.