Gallery: Billboard Awards 2014

Carrie Underwood holds the Milestone Award backstage at the 2014 Billboard Music Awards in Las Vegas. Photo: Steve Marcus/Reuters

Singer Robin Thicke performs "Get Her Back" at the 2014 Billboard Music Awards in Las Vegas. Photo: Steve Marcus/Reuters

Jason Derulo (R) and 2 Chainz perform "Talk Dirty" at the 2014 Billboard Music Awards in Las Vegas. Photo: Steve Marcus/Reuters

Jason Derulo (bottom, C) performs "Talk Dirty" at the 2014 Billboard Music Awards in Las Vegas. Photo: Steve Marcus/Reuters

Jason Derulo performs "Talk Dirty" at the 2014 Billboard Music Awards in Las Vegas. Photo: Steve Marcus/Reuters

Robin Thicke accepts the award for top R&B song for "Blurred Lines" at the Billboard Music Awards at the MGM Grand Garden Arena. Photo: Chris Pizzello/AP

Singer Miranda Lambert performs "Somethin' Bad" onstage at the 2014 Billboard Music Awards in Las Vegas, Nevada. Photo: Steve Marcus/Reuters

Rapper Whiz Khalifah presents top R&B song onstage at the 2014 Billboard Music Awards in Las Vegas. Photo: Steve Marcus/Reuters

Katy Perry is shown on a large screen as she accepts her award for Top Female Artist via satellite at the 2014 Billboard Music Awards in Las Vegas. Photo: Steve Marcus/Reuters

Singer Lorde accepts the top new artist award onstage at the 2014 Billboard Music Awards in Las Vegas. Photo: Steve Marcus/Reuters

Ricky Martin performs "Vida" at the 2014 Billboard Music Awards in Las Vegas, Nevada. Photo: Steve Marcus/Reuters

Shakira performs at the Billboard Music Awards at the MGM Grand Garden Arena. Photo: Chris Pizzello/AP

Shakira performs "Empire" onstage at the 2014 Billboard Music Awards in Las Vegas, Nevada. Photo: Steve Marcus/Reuters

Jennifer Lopez enters the stage as she performs at the 2014 Billboard Music Awards in Las Vegas. Photo: Steve Marcus/Reuters

Pitbull performs at the start of the 2014 Billboard Music Awards in Las Vegas, Nevada. Photo: Steve Marcus/Reuters

Rapper Nicki Minaj arrives at the 2014 Billboard Music Awards in Las Vegas, Nevada. Photo: L.E. Baskow/Reuters

Singer Kelly Rowland arrives at the 2014 Billboard Music Awards in Las Vegas, Nevada. Photo: L.E. Baskow/Reuters

Gerard Pique, left, and Shakira arrive at the Billboard Music Awards at the MGM Grand Garden Arena. Photo: John Shearer/AP

Model Kendall Jenner arrives at the 2014 Billboard Music Awards in Las Vegas. Photo: L.E. Baskow/Reuters

Rapper Wiz Khalifa and his wife, model Amber Rose, arrive at the 2014 Billboard Music Awards in Las Vegas. Photo: L.E. Baskow/Reuters

Recording artists Ben McKee, Dan Reynolds, Wayne Sermon and Daniel Platzman (L-R) of Imagine Dragons arrive at the 2014 Billboard Music Awards in Las Vegas. Photo: L.E. Baskow/Reuters

Country singers Carrie Underwood (L) and Miranda Lambert arrive at the 2014 Billboard Music Awards in Las Vegas, Nevada May 18, 2014. REUTERS/L.E. Baskow (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARDAWARDS-ARRIVALS)