Kacey Musgraves brought a very special guest on stage on Thursday (Feb. 28) at the historic Ryman Auditorium in Nashville, welcoming CeeLo Green for a live collaboration. This marks the second special act she has welcomed at the Mother Church of Country Music.

The pair sang Green's former duo Gnarls Barkley's iconic hit "Crazy." The song began starkly, with only Musgraves on guitar and Green's vocals echoing through the auditorium. Their vocals and background instruments soon turned more honky tonk.

Green was thrilled with the performance, and even shared fan pictures and videos to his Instagram Stories. He also turned to Twitter to share more fans reactions to the surprise appearance.

This was Musgraves' third performance of four during her Oh, What a World Tour 2019 stint at the Ryman Auditorium. On Wednesday (Feb. 27) Musgraves brought out Nashville native Hayley Williams of Paramore to perform the Cyndi Lauper hit "Girls Just Wanna Have Fun." The crowd erupted, and fans online were equally quick to freak out.

Musgraves has been collaborating frequently recently. She appears as a co-producer and collaborator on Brooks & Dunn's upcoming album Reboot. The trio performed "Neon Moon," a song Musgraves has covered in her live shows previously. She also was featured on the new record from another Nashville act, Judah & the Lion. The alternative-pop band were thrilled to have her take part in the music video and song "Pictures."

Musgraves' Oh, What a World Tour 2019 kicked off in Indianapolis in January, and it's slated to run through Sept. 28, when it wraps in New Orleans.

Watch: Kacey Musgraves Performs "Rainbow" at the 2019 Grammys: 

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