Eric Clapton has released a cover of "Always on My Mind" in tribute to Willie Nelson, who celebrated his 90th birthday earlier this year.

The guitar legend collaborated with country singer Bradley Walker on the track, which also includes additional guitar work by Ronnie Wood. Nelson celebrated his 90th birthday in April with a pair of star-studded concerts at Los Angeles' Hollywood Bowl.

You can watch the song's video below. The clip includes a montage of photos and videos of Nelson through the years.

READ MORE: Top 10 Eric Clapton Songs

"Dear Willie, Here's to 90 years and many more. Love, Eric and Bradley," the text in the video reads.

A Brief History of 'Always on My Mind'

"Always on My Mind" was written by Wayne Carson, Johnny Christopher and Mark James, and was first released by Gwen McCrae in 1972. Elvis Presley recorded a popular version that same year. Nelson's hit cover didn't arrive until a decade later in early 1982, but it quickly shot to the top of the country chart.

Nelson's take reached No. 5 on the Billboard Hot 100 and earned three Grammy awards in 1983: Song of the Year, Best Country Song and Best Male Country Vocal Performance.

"'Always on My Mind' bowled me over the moment I heard it, which is one of the ways I pick songs to record," Nelson wrote in 1988's Willie: An Autobiography. "There are beautifully sad songs that bowl me over ... haunting melodies you can't get out of your mind, with lines that really stick."

Eric Clapton Albums Ranked

Eric Clapton had already carved out a respectable career for himself before he issued his first solo album.