Ali Bacher, the last South Africa skipper to win a series against Australia in the republic, says disgraced captain Steve Smith and his ball-tampering team are "incredibly stupid".
Bacher led South Africa to a 4-0 whitewash over Bobby Simpson-skippered Australia in the 1969-1970 season.
"In this age of a thousand cameras, it was stupid to even think of doing it (ball tampering), and incredibly stupid to go through with it," he told the South African media.
TV cameras caught Cameron Bancroft trying to change the condition of the ball last Saturday in Cape Town using a piece of grit-encrusted sticky tape during a Test won by South Africa.
Smith later admitted he hatched the plot to cheat with the unnamed "team leadership" and is now facing disciplinary action, possibly later Tuesday.
Reports say Smith and vice-captain David Warner could be banned for 12 months and sent home in disgrace.
"You have to put the blame on the captain and I believe Cricket Australia will think long and hard about taking it further than the one-Test ban Smith has already got," said Bacher.
"I feel sorry for Cameron Bancroft because he would have been acting under instructions. If the leader of the team says you must do that, what option do you really have?