Prince may have had no closer collaborator than Morris Day, who met the future megastar when the two were teenagers and later played a role in his rise to fame.
Now, he's sharing his unique insight into the Purple One in a new autobiography.
Titled "On Time: A Princely Life in Funk," the book explores Day's "lifelong friendship and years of musical partnership with Prince, from their early days on the Minneapolis scene to selling out stadiums and duking it out as rivals in Purple Rain," the publisher says.
The leader of The Time, the band Prince formed as a side project, his career was intertwined with Prince's, and he would even star alongside a movie with Prince.
The autobiography is making headlines partly because of the stories it tells about Day's personal conflicts with him.
"On Time" takes a unique approach to this, with parts written in Prince's "voice." The publisher says this allows him to "protect his own legacy" and "to counter Morris’s interpretations of events.
Some of those events were dramatic, to say the least.
In one story, "Day turned up late and Prince exploded, shoving him," leading Day to throw a punch at the star," he said in an interview with New York Post. The two were separated before it could land, though.
“Of course it would have went my way,” he joked to the Post. “I outweighed the dude by a good 25 pounds!”
The book was released on Tuesday.