Performing with members of his longtime backing band The Cadillacs, the evergreen entertainer rolled back the years.
There was plenty of slapstick fun too, such as band members throwing undies onstage, which had the largely grey-haired crowd in gales of laughter.
"This age group has grown up with us and the music takes them back to a time they dig," Sharplin said after the concert.
"I've always been into the nostalgia of music and we all love going back and remembering the good old days." Sharplin (61) said he still enjoyed entertaining as much as when he started out 45 years ago.
"Putting smiles on strangers' faces is the best job in the world and that's what we do.
"Singing is good for your soul and it's good for other people's souls.
"I started my first band in 1967, when I was 16.
"It's been my way of life and I'm not going to stop."
The Operatunity national tour concert also featured Geoffrey Hughes, Tamsyn Miller and Cadillacs Ray Eade, Peter Wood and Bruce French.
