Blues, who it would be fair to describe as a 'yo-yo' club of late, could secure their third promotion to the top-flight in the last seven years by beating Preston this weekend, erasing the memory of two hurtful relegations.
And McLeish does not envisage having to provide much of a teamtalk to raise motivation in the home dressing room come Saturday.
"It will be a tough game and, quite simply, our players know that there is a phenomenal opportunity in front of them, an opportunity of a lifetime," said McLeish in the Birmingham Mail.
"If they do the business, in front of their own fans, they can get automatic promotion - which would be fantastic. Their aim will be to get back to the Premier League this weekend and also make the Birmingham fans happy. That's one of the rewards of the job - making fans happy, making people happy.
He added: "I know the players, the attitude they've got - we've talked about their steel all season - they really want it, they really want to get promotion. It's not a God-given right, it's not guaranteed, but there has been, and there is, a real focus about them."