Keith Urban turned to Instagram to pay tribute to one of his biggest influences, Don Williams, after the country legend died on Friday (Sept. 8).

Urban shared a video of himself with Williams clip from their "Imagine That" music video. "Imagine That" appeared on Williams’ And So It Goes album in 2012, and the video for the song shows Urban and Williams performing the song together, as well as laughing between takes.

"I cannot put into words the depth of sadness I feel right now at hearing of Don’s passing," Urban writes to accompany the clip.

Urban has frequently cited Williams' music as one of his primary influences. His father was a huge Williams fan when Urban was growing up, and the singer says that made a deep impression on him as to how an artist should record his songs.

"Don Williams’ records I grew up listening to, ‘cause of my dad," Urban tells the Boot. "Those records have that strong down beat, back beat, and little in-between rhythmic thing."

"That sounds like my childhood," he added.

Williams had a strong influence on "Blue Ain't Your Color," which became one of the biggest hits of Urban's career when he released it as the fourth single from his 2016 album Ripcord.

"On a song like 'Blue Ain’t Your Color,' it’s a very stark minimalistic way of recording, which really comes from those records that Don and Garth Fundis did, they’re really incredible albums. To go back and listen to those, which I do very often, is to be reminded of just how little you need," Urban reflects.

Williams enjoyed a string of country hits from 1974 and 1991 that included "Good Ole Boys Like Me," "It Must Be Love," "I Believe in You," "Tulsa Time," "Back in My Younger Days," "You’re My Best Friend," "Lord, I Hope This Day Is Good," "Some Broken Hearts Never Mend" and more. He took home the CMA Award for Male Vocalist of the Year award in 1978, and "Tulsa Time" won Record of the Year at the 1979 ACM Awards.

Williams announced his retirement in 2016. He died on Friday after a brief illness at the age of 78.

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