Lady Gaga and Sting 'Stand by Me' at iheartradio Festival

Pop stars team up in Las Vegas

Sting joined Lady Gaga onstage at the iheartradio Music Festival in Las Vegas on Saturday to perform the Ben E. King classic "Stand by Me" and the former Police man's own hit, "King of Pain." "Sting is one of my very favorite people in the world," Gaga said before the two launched in. "When I started in this business, I started to meet really amazing, incredible musicians, like real legends, but they're not always very nice. But Sting is one of the most kind and loving people I've ever met."