He might be famous as Guns N' Roses punk bassist, but Duff McKagan has always professed a love for music in many forms, with a longstanding relationship to both Sabbath and Ozzy Osbourne, even playing on the latter's last two albums.

I am so privileged to have spent most of my life with him," Terence “Geezer” Butler said of his late bandmate and friend

"I didn’t realize then that I would never see Ozzy again after that night," Butler writes of the July 5 "Back to the Beginning" show in England.

In an emotional essay, Geezer Butler recalled his decades-long friendship with Ozzy Osbourne and Black Sabbath's final rehearsals.

Osbourne, who battled Parkinson’s before his death, sat onstage in a black leather chair as he performed for the 42,000-person crowd. He sang five songs by himself, before he was joined by his former bandmates for four Black Sabbath songs.

Black Sabbath through a prolific solo career — how the heavy metal icon's music peppered the soundtrack of one writer's life.