Global Citizen

Ariana Grande Surprises Coldplay Fans Onstage: Watch

Coldplay also debuts a new song, 'Amazing Day.'

NEW YORK -- When Chris Martin asked his kids, Apple and Moses, who they wanted to come onstage during Coldplay's set at Saturday's (Sept. 26) Global Citizen Festival, he said there were a few weeks of deliberation. But when Ariana Grande came onstage, you know they made the right choice.

Grande, dressed in a black and white striped pant suit, and Martin, in a sweaty blue T-shirt, duetted her song "Just A Little Bit Of Your Heart" off 2014's My Everything. Coldplay had only learned it a few hours before, but the pair harmonized seamlessly as Grande took some of the higher vocal runs with ease.

Coldplay also debuted a new song, "Amazing Day," at the end of their set. "This is about the wonderful things on earth..." Martin cut himself off, tangling his words, and launched into the slow, uplifting ballad that may or may not be on their upcoming album, A Head Full Of Dreams.

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This isn't the only time Martin will be making a Global Citizen appearance -- the Coldplay frontman has signed on to curate the festival for 15 years. And he's definitely no stranger to surprise duet performances either. Just last night, he and Ed Sheeran wowed a Boston crowd with their joint renditions of "Yellow" and "Thinking Out Loud." Sheeran also brought him out during his own Global Citizen set later on to repeat their "Thinking Out Loud" duet.

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