The anticipation for the Billboard Awards continues to build with yet another performer announcement. Iggy Azalea will perform her chart-topping hit "Fancy" and she's also set to join Ariana Grande onstage for "Problem," the first single off the singer's new album. Considering the fact that Grande's a younger version of Mariah Carey and Azalea practically oozes confidence and attitude, this performance should definitely rank among the best of the night. For one, the "Fancy" video was nothing short of epic due to its incorporation of scenes from Clueless. It'll be interesting to see if Azalea's set will transform the stage into a mini-version of Bronson Alcott High. Grande's vocals are awesome, and unlike some of her singing counterparts, her voice isn't simply a product of severe studio manipulation. In fact, she sounds unbelievably great live. But judging by her iHeartRadio Music Awards set, she may need a little help in the performance arena. There were a few moments where she looked downright awkward onstage, particularly throughout the dance routine during Azalea's rap. Fortunately, the 23-year-old should have plenty of energy to help fuel Grande's performance, especially since she just became the first female rapper to ever have two songs simultaneously in the top five of the Top 100 chart.Considering the aforementioned performance produced a Twitter frenzy over purported celeb reactions, surely all eyes will be on Grande and Iggy to see whether they can pull off a set that doesn't convince everyone that Rihanna is laughing at them, or that they are boring Luke Bryan and Blake Shelton to tears.By now, Azalea has plenty of tour experience and just put on a live stream performance for Red Bull, and hopefully Grande's taken some time to assess the shortcomings of her iHeart show. With a few minor adjustments, the powerhouse singer's silky smooth vocals and Azalea's finesse and feisty raps should make pulling off a noteworthy performance no problem.