While John Legend, Meghan Trainor, Tyrese and Luke Bryan held their own, singing classics like "Easy" and "Brick House," it was Lovato who stole the show.
Rocking a cleavage-baring sharp white blazer, Lovato showed off her powerful pipes during the ballad that had Richie himself -- and the GRAMMYs audience -- absolutely floored.
Before the GRAMMY telecast kicked off, Lovato spoke to ET on the red carpet about her awards show debut.
"I'm just excited to be here," she told ET's Nancy O'Dell. "I've always wanted to make it here and I always wanted to wait [for] my first time until I was either performing or presenting. I'm here and I'm excited!"