After a few months of playing to jam-packed audiences on their We Own the Night Tour, Lady Antebellum's Charles Kelley was ready to cut loose and enjoy the band's last U.S. tour stop in Milwaukee on Saturday night (June 30). To close out his portion of the show, opener Darius Rucker launched into a performance of Prince's 'Puple Rain,' but he was almost derailed when vocalist Charles Kelley walked on stage dressed as Prince.

As Rucker was singing the song's chorus, Kelly entered from stage right wearing a purple velvet jacket, tight jeans and a huge, black, curly wig. Even after spotting Kelley in his '80s getup, Rucker managed to get through another verse before doubling over with laughter.

Ready to go, Kelley picked up where Rucker left off, using his robust voice to imitate Prince's wailing vocals for a few bars of the song as the crowd screamed and hollered in approval. To end the tune, a more composed Rucker took to the mic again, and the two country music stars finished out the duet in style while the rest of the Antebellum trio -- Dave Haywood and Hillary Scott (and her dog Hobbs) -- watched from the back of the stage.

Lady A's U.S. leg of the We Own the Night Tour has closed, but the award-winning trio will pick up across the pond next week with new opener Kacey Musgraves in tow. The 'Wanted You More' hitmakers will play shows in several European countries and Australia before returning to the states in October.

Watch Charles Kelley and Darius Rucker Sing 'Purple Rain'