But, he said, Cornelius' career took off as the significance of the show grew and grew.
"Over time, he became the show to be on if you wanted to be anybody in this business," said Butler.
Butler, who played with the likes of Otis Redding and was once a member of the Impressions, along with Curtis Mayfield, sang for Cornelius at the 40th anniversary show. Along with two original Impressions and the singer who replaced the late Mayfield, Butler performed his 1969 hit "Only The Strong Survive."
Butler recalled Cornelius walking a little slower, but otherwise seeming to be in good health and in good spirits.
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