There is a crucial thing to know about “Crucial," the gorgeous ballad that appeared on Prince's 1998 vault compilation, Crystal Ball: Jazz legend Miles Davis did not play on the track and the trumpet or flugelhorn part that’s attributed to him is actually a saxophone solo by Eric Leeds. Still, you can’t blame bootleggers for trying to move some units with the prospect of such a cherished collaboration.

As noted earlier in this series, the only known Prince song featuring Davis is an unreleased track, “Can I Play With U?” The answer to that song's question, sadly enough, was “not really." As tantalizing a prospect as it was to imagine Prince and Davis jamming in the studio, Davis recorded his part of the song separately. Davis also recorded three Prince-penned songs with his own band, none of which were deemed suitable for release. The two did, however, play nicely together one time, in a live performance jam at Paisley Park.

“Crucial” was officially released in 1998, more than a decade after its creation. According to PrinceVault, initial tracking took place on Sept. 13, 1986 at Prince’s Galpin Road studio, days after the end of the Parade tour and weeks before Prince disbanded the Revolution. When it finally saw the light of day, it provided a fond flashback for fans of Prince’s '80s work who had suffered though his awkward, rap-heavy, New Power Generation era.

Hear Prince Perform "Crucial"

In Mobeen Azhar’s book Prince: Chapter and Verse -- A Life in Photographs, Prince engineer Hans-Martin Buff tells the story of Crystal Ball, “(Prince) gave me a list of songs and I had to find them. We went into the fabled vault. It starts from the left and it has rows and rows of tapes that are chronologically labeled. On the right is the newest stuff.” After Buff emerged, he says they edited and cut a lot but did little mixing.

Two circulating versions of “Crucial” clock in above the seven-minute mark. For the first, Prince asked Leeds to lay down a sax solo on Nov. 6, 1986 as a guide track for a future guitar solo. Despite the prospects of pouring his heart and soul into a lost cause, Leeds slays his solo, marking one of many peaks in his involvement with Prince across many bands and projects. The official version, focusing on Prince’s guitar solo, is trimmed to a hair over five minutes.

In the liner notes for Crystal Ball, Prince said “Crucial” was intended for Sign 'O’ the Times, before it was replaced by “Adore." Prince historian Per Nilsen suggests the song may have been intended for The Dawn, a musical, movie, album and/or spiritual experience that Prince long alluded to with the cryptic “may U live to see the dawn” message that graced many albums and the end credits to Purple Rain.

The Crystal Ball album itself had a bumpy road into consumers' hands because Prince missed a few crucial details when choosing an ambitious five-CD set to be the first album he sold, manufactured and distributed all on his own. In the book, Prince: The Man and His Music, designer Steve Parke told author Matt Thorne, “The original idea was to do an actual crystal ball, with the two halves separating and the CDs suspended in the middle.”

Fans who pre=ordered it through Prince’s love4oneanother website or the 1-800-NEW-FUNK phone line almost a year before it was released received it in the mail months after it arrived at retail in a traditional set complete with liner notes. Granted, the people who ordered it direct from Prince also received a bonus disc, Kamasutra, an instrumental album credited to the NPG Orchestra.