Career
Along with former bandmate, keyboardist/vocalist Jim Peterik, Sullivan co-wrote many of the group"s hits including "Eye of the Tiger" and "Burning Heart" from the Rocky III and IV movie soundtracks. Sullivan began playing guitar in his very early teens by sitting in on local garage band practices and helping with their equipment changes. Eventually he was allowed to play a little after band practice when members realized his serious interest, as stated by local piano/keyboard musician and Northlake, Illinois resident Jimmy Tranchitella.
He was part of the United States hard rock band Mariah in 1976 (Mariah Mariah united artists records UA-LA493-G).