City will secure their first top-flight crown for 44 years if they defeat relegation-threatened Queens Park Rangers on the final day of the season at the Etihad Stadium.
Roberto Mancini’s side are level on points at the top of the table but boast a superior goal difference.
Any slip by City will allow United, who are away to Sunderland, to claim a record 20th crown if they better the result of their neighbours.
Ferguson told reporters at a press conference in Manchester on Friday that he expects City to win.
But the long-serving United manager believes Mancini’s side could be damaged if they mess up at the final hurdle.
“We can only do our best and try and win the match. Hopefully something stupid happens to City,” said Ferguson, who revealed England defender Chris Smalling will miss Euro 2012 with a groin injury.
“On the face of it you expect City to win and so do I. But City have got to win. It’s an enormous challenge for them because the disappointment of losing the game would be unbelievable.
“It’s untold at this moment in time what effect it could have on them.
“It’s the last game of the season. It’s fantastic for the neutral, fantastic for the media but agony for both clubs although it will be more so for City if they lose it.”
Ferguson is hoping QPR, who will be relegated if they lose and Bolton win at Stoke, take a leaf from the book of his former club Aberdeen.
The Scot led Aberdeen to a suprise victory over Real Madrid in the European Cup Winners’ Cup on May 11 1983 in Sweden.
“Do you know what I was doing 29 years ago today?” added 70-year-old Ferguson.
“I took a wee team called Aberdeen to Sweden to beat Real Madrid in a European final with 11 players home-bred, with the oldest player 27-years-old. That’s QPR’s challenge – to do an Aberdeen.
“Of course the odds are stacked against them, City are in good form and are at home. But as long as human beings are human beings you never know. You hope something stupid happens.
“QPR are fighting for their Premier League future.
“They have invested a lot of money to get where they are. But probably most of the players will be put on the list, (if they go down) all of the players will have their salaries halved from what I can gather, things like that.”