Dennis Tueart has urged Sunderland chairman Ellis Short to stick with manager Steve Bruce.
Bruce remains under pressure despite recent results.
"Patience is the word for Steve," said Tueart, who won the FA Cup with Sunderland in 1973. "He has brought in a lot of players and they need time to gel together.
"The biggest problem with foreign owners not understanding football is that they don't seem to recognise there are only four trophies to win.
"So if there are 10 foreign owners, they can't all win. They have to understand that.
"Nothing happens instantly. If you want to build a tower, you build it on solid foundations. That takes time."
And while he has no axe to grind against Short, Tueart is distrustful of the businessmen who have arrived in the sport believing they hold the answer to age-old questions about success.
"Football seems to have attracted all these mercenary career builders, who just want to get their nose in the trough without any understanding of the game itself," he said.
"They always seem to think they can just turn things round. That is dangerous. Football is not like that."