After Christina Aguilera contacted A Great Big World to be a part of their song Say Something, the duo was surprised to find out she had no intention of having a solo.

"We actually were thinking that she would take a verse and do all this belting stuff at the end, but she didn't want to do that, she wanted to let the song just be," band member Chad Vaccarino told The Hollywood Reporter. "It makes you kind of feel the longing [of the song]."

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The group's other member, Ian Axel, added: "She wanted to let it breathe and just be open, and we've never heard her sound so vulnerable. From what she's told us, she's in a different place in her life, and she only wants to take on projects that inspire her, so we're super honored."

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The group performed the song on The Voice along with Aguilera earlier in November. They also performed it without Aguilera at the Victoria's Secret Fashion Show on Nov. 13.

Aguilera explained her desire to work with the group in a behind-the-scenes video released on Nov. 1.

"This song Say Something sort of is coming to me at a time when I'm feeling very inspired," she said in the clip. "I'm only taking on projects that feel good to me and represent as always a purpose of the here and now in my life and that's what this song Say Something actually does for me."

The song will appear on the band's full-length album, Is There Anybody Out There?, expected on Jan. 14 on Epic Records.

Tags: Christina Aguilera A Great Big World