This is one of those random events that leave a smear of residue, a small fluff ball of memory that clings to the fabric of life when so much else is washed away.
The young man in the sweatshirt and grubby blue jeans stands out amidst the genteel splendour of the opera house, an ugly intrusion like a gaudy weed in a bed of delicate perennials.
Decline and renewal are the basic motors of the pop music scene. Always have been, always will. Bands come and go, change direction, reinvent themselves for better or worse.
It begins in October 1979 when, over two consecutive nights, I went to a concert by ex-Genesis guitarist Steve Hackett in Bradford and then, the following evening, saw Supertramp playing at Wembley Arena in London.