Kacey Musgraves and Willie Nelson took the stage together Wednesday night (Nov. 13) at the 2019 CMA Awards to perform "The Rainbow Connection," a tune that first came to prominence 40 years ago.

Backed by a swelling string section, a guitar-wielding Nelson started the song off solo before Musgraves walked out mid-performance to turn the song into a touching duet. "The Rainbow Connection" originally hails from 1979's The Muppet Movie. In that film, the song was performed by Kermit the Frog as voiced by the late Muppets creator Jim Henson.

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Since that time, however, the number's become somewhat of a signature song for the 86-year-old Nelson. In 2001, it appeared as the opening track on the country legend's Rainbow Connection album.

For Musgraves, her collaborative CMAs performance with Nelson represented a "full-circle moment" after the pair previously collaborated on Musgraves' 2016 Christmas album A Very Kacey Christmas, the two joining forces on the song "A Willie Nice Christmas."

Musgraves and Nelson's 2019 CMA Awards performance was his first since 2012. Nelson is a 10-time CMA Awards winner, most recently in 2017, for "Funny How Time Slips Away," his collaboration with Glen Campbell, which won Musical Event of the Year. The CMA's Lifetime Achievement Award is also named in his honor, as he was its first recipient.

Musgraves, meanwhile, entered the 2019 CMA Awards with nominations in the Female Vocalist of the Year, Song of the Year and Music Video of the Year categories. In 2018, her album Golden Hour won Album of the Year.

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