It took a while, but Prince's long-distance infatuation with Chaka Khan led to a close working relationship – and Khan's signature song.

Both signed with Warner Bros. in the late '70s. For Prince, however, the connection went back much further. He religiously followed Khan's broadcast performances, collected her 45s, and even had a poster from her early years with the R&B group Rufus. One of Prince's first demos was a take on "Sweet Thing" from 1976's Rufus featuring Chaka Khan.

In a later talk with the Philadelphia Daily News, Prince admitted to being "a fan and a fanatic, too, because I used to run home and see everything she was on."

Khan's work continued to inform his career. During the sessions for Prince's first album, he reportedly listened to Rufus for inspiration. Years later, a huge mural at Paisley Park Studios featured Prince surrounded by a series of key influences – including, of course, Khan. "He absolutely loved that girl," engineer Steve Fontano once told biographer Per Nilsen.

Perhaps inevitably, their first meeting – long before Chaka Khan turned "I Feel For You," from 1979's Prince, into a No. 3 1984 smash – was an awkward affair.

"He called me at my hotel," Khan told Billboard in 2016. "I was and still am very good friends with Sly Stone. He knew that, I guess, 'cause he mimicked Sly's voice completely. I was completely fooled. He said 'This is Sly; I'm down at Electric Ladyland.' 'OK, I'll be right down!' And that's how he got me down to the studio. I get there and there's nobody there except for one little guy in this room with a guitar. And I said 'Do you know where Sly is?' He said to me, 'Hi, I'm Prince; I called you.' I was very pissed. And that's how we met."

This chance encounter eventually helped save her career.

Listen to Chaka Khan Perform 'I Feel For You'

By the early '80s, Khan had long since left Rufus, and her solo career was losing steam. It had been five years since Khan kicked off her solo career with "I'm Every Woman," and almost a decade since her hit 1974 take on Stevie Wonder's "Tell Me Something Good," which arrived as part of a string of well-received albums with Rufus.

More recently, she'd been dabbling in distinctly uncommercial sounds on albums like 1982's jazzy Echoes of an Era. Her label was growing impatient.

Khan and long-time producer Arif Mardin turned to Prince for inspiration, but added a series of distinctly modern touches. Their take on "I Feel For You" included of-the-moment elements like electro-funk synth stabs, a sample of Wonder's "Fingerprints Pt. 2" and a classic rap ("Ch-ch-ch-chaka-chaka-chaka Khan") from Melle Mel of Grandmaster Flash. It worked.

"'I Feel For You' is obviously a song that appeals to a lot of the younger kids. And the stuff that Arif and I have been doing for the past five years hasn't," Khan told Billboard back then. "We've been scratching each other's backs, doing a lot of jazz and having a good time doing what we wanted to do. We didn't really have an ear tuned to the rest of the world or the market. With this album, Warner Bros. did say, 'We'd like to sell some albums now, guys, if you don't mind.'"

In truth, others had attempted to turn this song – which was originally presented in Prince's nervy early style – into something more than a funky deep cut. The Pointer Sisters' take, produced by Richard Perry for 1982's So Excited, only hinted at where the song could go. Rebbie Jackson's contemporary version, from 1984's Centipede, sank without a trace.

Khan's relationship with the song, and the artist, ran deeper – and that gave Khan the freedom to truly make "I Feel For You" her own. "It has to already feel like it's mine way before I record it," Khan said in I Got Thunder: Black Women Songwriters and Their Craft. "Also, I've been careful to sing songs written by artists whom I have a deep respect and deep admiration for, so that when I come to their songs it falls together in the most natural way."

Listen to the Pointer Sisters Perform 'I Feel For You'

Prince was apparently set to play guitar on Khan's session, but had scheduling problems as work continued on Purple Rain. Stevie Wonder, another old friend, ended up completing things with a turn on the chromatic harmonica that was recorded on April 4, 1984, the same day he attended Marvin Gaye's funeral.

"I Feel For You" remained in Billboard's Hot 100 for 26 weeks, topping the Cash Box singles chart, and both the U.S. Dance and R&B charts in late 1984. It went to No. 1 in the U.K., as well. Prince subsequently claimed a songwriting Grammy for Best R&B Song, cementing his relationship with Khan.

He later signed her to a record deal, releasing Come 2 My House on NPG Records in 1998. A supporting tour found the pair performing "I Feel For You" together on stage. "One of the pleasures of my life," Prince told Guitar World in '98, "is being able to work with some of my musical heroes – and, in doing so, pay back some dues."

Khan then joined others who made the sad pilgrimage to Minneapolis for a 2016 tribute concert after Prince's sudden death. There, she was joined once again by Wonder for an emotional new update on "I Feel For You."

"We thought very much alike; we were very kindred, in many, many ways," she told the Associated Press. "Musically, I like to think that God provided me with a kindred spirit for me to actually work with, and to get to know and love for a short while."