Songwriter Jonathan Cain & guitarist Neal Schon recall Prince reaching out about similarities to their song "Faithfully": "I just thought it seriously showed the kind of caring, classy guy Prince was," Cain tells Billboard.

We've been hearing plenty of "Purple Rain" in the days since Prince's shocking death, from onstage tribute performances to last-minute screenings of the 1984 film by the same name around the world. But it turns out "Purple Rain" the song might not have happened without a little cooperation from the members of Journey.

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Singer/songwriter Jonathan Cain tells Billboard that he was notified in early 1984 that Prince wanted to speak with him. Curious, Cain went to Columbia Records' offices in Los Angeles and took a call from Prince, who told Cain, "I want to play something for you, and I want you to check it out. The chord changes are close to 'Faithfully'" -- a top 20 single from Journey's 1983 album Frontiers -- "and I don't want you to sue me." After listening, Cain says, "I thought it was an amazing tune, and I told him, 'Man, I'm just super-flattered that you even called. It shows you're that classy of a guy. Good luck with the song. I know it's gonna be a hit.'

"And it was 'Purple Rain.'"

The two songs definitely share more than just similar chords, including the wordless outer vocals and the tone of the guitar solos. "Prince felt, I guess, it was obvious enough that he was worried we were going to sue him," Journey guitarist Neal Schon recalls. "I think he called our office asking about it and we all talked about it and everybody said, 'Nah, it's the highest form of flattery. Let it go.'" But Cain never had a moment's second thought about even asking for a co-writing credit on the anthem. "No, no, that'll just bring bad juju on you, and you don't want to do that," Cain says. "I just thought it seriously showed the kind of caring, classy guy Prince was. He wanted to check in with Jonathan Cain and make sure I wasn't going to say, 'That sounds like 'Faithfully.'" There's so many other things that have come down the pike that were more of a rip-off, that have stolen Journey songs. There was a One Direction song I was upset about and I just let it roll. But that particular phone call [from Prince] was amazing."

There were perks for playing ball too. "He got me these amazing seats at the Purple Rain [Tour] show when he played the Cow Palace in San Francisco, and I thought it was ridiculous how cool it was," Cain says.

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"Faithfully" was the second single from Frontiers, peaking at No. 12 on the Billboard Hot 100. The song was a late addition to the album, after producers Mike Stone and Kevin Elson asked for another power ballad for the set. "The next day, [Cain] brings in this song that just came to him in the middle of the night and wrote down all the lyrics and had the basic song put together," remembers Schon, who nevertheless had trouble coming up with a solo. "I didn't know what to do on it so I said 'I'll just sit this one out,' and everybody went, 'No, no, just play, play whatever comes to your mind,'" the guitarist says. "So I wrote out my own little chart and I went out, and I believe we played the song twice and that was it. There were no vocals on it yet. Steve [Perry] came in the next day and kicked everybody out of the studio 'cause he wanted to sing it by himself."

The Journey members subsequently learned that the similarities between the "Purple Rain" and "Faithfully" guitar solos were not coincidental either. "There's a guy that Jonathan and I both know in Minneapolis who worked with Prince in the last few years," Schon says, "and he told Jon to tell me that Prince was talking about my guitar playing, how it really moved him and how he liked my playing. It was just so cool."

"How much he loved Neal Schon is crazy," Cain adds. "He studied Neal for so many years, learned his licks and made them his own. You can hear it on ('Purple Rain') for real."