Kacey Musgraves, Willie Nelson Duet at 2019 CMA Awards [WATCH]

Kacey Musgraves and Willie Nelson teamed up for a tender moment at the 2019 CMA Awards. The pair of Texans performed "Rainbow Connection," the song that Kermit the Frog made famous in The Muppet Movie in the 1970s.

Backed by an orchestra, Nelson strummed his acoustic guitar as he and Musgraves sang. His gravelly sound and Musgraves's pure vocals wove together beautifully, and the simple presentation of "Rainbow Connection" paid homage to the beauty of the whole performance: the lyrics, vocals and palpable friendship between the two singers.

When the song ended, Nelson whispered "beautiful" to his singing partner. It was, truly, a beautiful rendering of the iconic song.

Nelson and Musgraves have collaborated previously, too: Musgraves 2015 sophomore album, Pageant Material, features a cover of Nelson's track "Are You Sure."

Musgraves and Nelson's performance was Nelson's first at the CMA Awards since 2012. Although he still is actively touring, televised performances from the country icon have been few and far between in recent years. Earlier this year, the 86-year-old had to cancel multiple performances due to "breathing problems," and has dealt with issues stemming from emphysema and pneumonia sporadically over the past five years.

Musgraves just wrapped up her lengthy Oh, What a World Tour in support of her hit record Golden Hour. The Texas native is nominated in the 2019 CMA Awards Female Vocalist of the Year category, and for Song of the Year and Music Video of the Year.

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