And Rudess reports that he was lining up a career as a professional classical pianist until he heard ELP's 1971 album Tarkus for the first time. Rudess tells Freqs TV: "This has been a major, sad event in my life because it was completely unexpected. Keith was my keyboard hero. He really was the person who I looked up to. His music changed my path of life.

"I was deeply in the classical path - I was going to be a professional classical pianist. I was going into the college division at The Julliard School. But I waved goodbye because I was already into synthesisers and Tarkus - I was into other things that didn't relate at all to what I had been doing."

Rudess says that Emerson "opened the door" for him to explore a different type of music and adds: "The Emerson thing hit me like a ton of bricks because this person that was not only my keyboard hero became a friend of mine.