As tributes to the late Merle Haggard continue to roll in, one anecdote keeps coming up: That time Haggard was an inmate at San Quentin and saw Johnny Cash perform one of his famous prison concerts.

Haggard devotees often point to that as a turning point for the hard-living country music star. Haggard's teenage years were a blur of petty crime, vagabond travel and juvenile detention; arrested for robbery in 1957, he was doing hard-time and yes, really did turn 21 in prison — but he had serious music skills, and seeing Cash on stage inspired him to get his life on track.

Photos: The life and career of country music legend Merle Haggard

Merle Haggard performs at the Aladdin Theater for the Performing Arts in Las Vegas while touring with Willie Nelson and Ray Price. Haggard began playing guitar at age 12. (Ap Photo/LAURA RAUCH)

Really? Honestly, it's one of those tales that just seems too perfect. Two of country music's most legendary outlaws just happened to cross paths in such suitable-for-the-biopic fashion?

Merle Haggard, one of the kings of country, passed away at the age of 79. (Erin Patrick O'Connor/The Washington Post)

Turns out, sometimes moments really are just that magical. Country music may be filled with myths, but Michael Gray, editor for the Country Music Hall of Fame and Museum, assures us there's no reason to doubt this one.

While Cash didn't record his famed prison shows at Folsom and San Quentin until the late 1960s, he really did tour prisons as early as the late 1950s. The typical story going around is that Haggard saw him in early 1958. This timeline seemed questionable, since he didn't enter San Quentin until March of that year.

But a database of Johnny Cash live performances indicates he performed at San Quentin on New Year's Day of both 1959 and 1960 — squarely within Haggard's tenure at the prison. Not only would he have had the chance to see him perform, it's hard to imagine him passing up the chance.

Haggard also frequently spoke about the experience and wrote about it in his 2002 autobiography, "My House of Memories: For the Record." When asked if he had any positive experiences in prison, Haggard would always talk about seeing Johnny Cash and how it helped him become a better man.

"He kept getting in trouble at San Quentin. . . Seeing Johnny Cash encouraged him [to say] 'You know what, okay, I need to grow up and get my act together,'" Gray said. "It encouraged him to really just focus on music and quit getting in trouble and get out of prison and get on with his life and career."

Even after that, Cash helped Haggard about a decade later. Haggard was out of prison and an established country star when he appeared as a guest on ABC's "The Johnny Cash Show" in August 1969. According to Gray, Cash encouraged Haggard to talk about his rough past on television, and signal to the audience his hits like "Mama Tried" were truly autobiographical. The dialogue on air went something like this, Gray said, after Cash brought up San Quentin:

Haggard: "Funny you mention that, Johnny."
Cash: "What?"
Haggard: "San Quentin."
Cash: "Why's that?"
Haggard: "The first time I ever saw you perform, it was at San Quentin."
Cash: "I don't remember you being in that show, Merle."
Haggard: "I was in the audience, Johnny."

Even though Haggard's prison time wasn't a secret, it was the first time he addressed it in front of a national audience, Gray said. ABC got letters from angry viewers, unhappy the network had an ex-convict on the air. But the whole appearance, as well as Cash's encouragement to be honest, influenced his career for the better.

In fact, Gray said, Haggard's tendency to confront personal struggles helped make him an icon — and "plays into that whole title of him being known a poet of the common man."

(This story has been updated to reflect the historic record on Cash's concert dates.)

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