While the two powerhouse singers are used to judging musical performances on The Voice, they are going head-to-head in a sing-off on the premiere of That's My Jam, a new NBC game show hosted by Jimmy Fallon. In a preview of the series' sneak episode, Ariana and Kelly show off their vocal prowess in a round of Mixtape Medley Showdown, covering random songs from iconic pop divas. Though Ariana has proven in the past that she can just about mimic anyone from Christina Aguilera to Shakira, it's clear that she senses some tough competition from Kelly. Ariana kicks off the challenge with a spot-on rendition of Britney Spears’ Oops… I Did It Again, before Kelly follows with an equally impressive cover of Shania Twain's Any Man of Mine. Each episode of That's My Jam features two teams of celebrities as they compete in music, dance and trivia challenges for charity.