A letter to two of Johnny Cash's children helped make Eric Church's show-stopping 2020 ACM Awards performance a reality. In fact, the set may not have even happened without it.

Back in July, Church shared a worktape of himself performing Cash's "Ragged Old Flag" into his own current single "Stick That in Your Country Song" with ACM Awards Executive Producer RAC Clark: the country superstar's idea for his 2020 ACMs performance. However, they'd need permission to use the Man in Black's song.

"As we got into it, we found the Cash estate and publishers are very protective," Clark shares in Country Aircheck. "No matter how much talking I did trying to get it cleared, it was a corporate wall."

So, Clark went to Church's team with a suggestion: He needed the singer to appeal to two of Cash's children, Rosanne Cash and John Carter Cash, both of whom are artists, too. Church sent his thoughts to the Cash clan — and it worked.

"I’m never going to share that letter, but it's the reason that performance aired," Clark explains. "His passion about what he wanted to say and why allowed them to entrust him with their father’s legacy."

The title track of Cash's 47th studio album, released in 1974, "Ragged Old Flag" was written by the Man in Black after President Richard Nixon's resignation. The spoken lyrics recount a conversation between and old man and a visitor to town: After the visitor disparages the town's courthouse and "ragged old flag," the old man recounts the flag's storied history.

"And the government for which she stands / Is scandalized throughout the land / And she's getting threadbare and wearing thin / But she's in good shape for the shape she's in / 'Cause she's been through the fire before / And I believe she can take a whole lot more," reads one verse that still feels particularly timely today.

Rather than have Church sing Cash's song, however, Clark and company found an instrumentation-free recitation of "Ragged Old Flag," which allowed Cash's words to be heard in his own voice during the awards show, with Church and his band playing behind him.

"There was a lot of sweat equity by a lot of people. Part of my job is to bring these things to life, but this was Eric’s vision," Clark says. "He pushed it over the top, and boy, did he deliver."

See Pictures From the 2020 ACM Awards Red Carpet:

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