"Even though we know it's inevitable, we never expect to suddenly lose close friends and collaborators," Cooper told Billboard. "Dick Wagner and I shared as many laughs as we did hit records. He was one of a kind. He is irreplaceable. His brand of playing and writing is not seen anymore, and there are very few people that I enjoyed working with as much as I enjoyed working with Dick Wagner.

"A lot of my radio success in my solo career had to do with my relationship with Dick Wagner," he continued. "Not just on stage, but in the studio and writing. Some of my biggest singles were ballads what I wrote with Dick Wagner. Most of Welcome to My Nightmare was written with Dick.