Ariana Grande Surprises 'American Idol' Contestant At His Most Embarrassing Moment

Austin Mahone also stepped in for an #IdolSelfie.

Last night was a star-studded "American Idol" (and I'm not just talking about the judges' panel). I'm talking Austin Mahone and Ariana Grande.

The two young stars hit up the reality competition last night. Austin was only there to take a selfie — but it wasn't any old selfie. Viewers were encouraged to take a selfie with their TV, which had Austin and Ryan Seacrest in the background.

Later in the night, when contestant Sam Woolf went onstage, he couldn't find the microphone. But instead of the whole flub turning into a super-embarrassing moment, Ariana showed up to save the day. Needless to say, Woolf was rather surprised. Ariana, in a black shirt-dress, gave him a hug before he took on his rendition of Ed Sheeran's "Sing."


Grande also hung out with Randy Jackson, which may have been the highlight of her night. Randy tweeted out a pic of their meet-up, while Grande joked to her fans about how he shot her down for a high five. Who's too cool now?