Summer of 1977.....Led Zeppelin...I believe "Physical Graffitti" tour. Chicago Amphitheater.
After about 3 songs Robert Plant announced they could no longer go on.....that Jimmy Page had a case of montezuma's revenge (flu).
Truth is, he could hardly stand up straight. Seemed completely wasted out of his mind staggering around the stage. Even though we all got our money back I lost a lot of respect for the band that night. Colossal waste of time.