The heavy rocker will release his first new solo album in a decade on 21 February, and after his wife Sharon Osbourne let it slip Elton would be among the guests, Ozzy explains his old pal plays piano on the collaboration, which debuted on Friday, January 10.
"It all just came together," Ozzy tells WENN. "When I was writing 'Ordinary Man', it reminded me of an old Elton song and I said to Sharon, 'I wonder if he would sing on it?' We asked and lo and behold, he agreed and sings and plays piano on the song."
"It was a lot of fun to do," Ozzy adds. "We recorded it quickly, which I haven't done since the first Black Sabbath album. This made it a different process, which I actually enjoyed."