Ariana Grande Skips Her Ponytail Hairstyle on 'American Idol'

Ariana Grande pops out on stage for a surprise appearance on American Idol on Wednesday (April 30) in West Hollywood, Calif.

The 20-year-old singer went for a different hairstyle for the appearance, letting her hair down instead of her signature ponytail style. She was there to surprise contestant Sam Woolf, who has said he has a crush on the singer.

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“had fun surprising Sam on idol tonight! thought his performance was great. thanks so much for having me @ryanseacrest,” she later tweeted.

Also in attendance that night was Austin Mahone, who dropped by to say hi to his pal Ryan Seacrest.

“Thanks for having me on @americanidol @ryanseacrest!! #iheartmahone,” he captioned an Instagram photo of the two.