Roberto Mancini’s side are in first place on goal difference with two games remaining after City’s 1-0 win against the Red Devils in the Manchester derby on Monday night.
The City manager insisted United were still favourites for the title despite the holders’ loss at Eastlands, but Ferguson rubbished the Italian’s claim.
“He can do what he likes at the end of the day,” Ferguson told United’s website.
“They’ve got to go to Newcastle and win that game and then I think they’ve won the league. Where he’s coming from, I’ve no idea unless he doesn’t think his team can beat Queens Park Rangers at home.
“We know what we’ve got to do is concentrate on our game. The good thing is we know what we’ve got to do – the only advantage we’ve got on Sunday is we’ll know exactly where we are and hopefully we can do something about it still.”
The 70-year-old admitted the derby defeat left United’s squad deflated in training this week, but Ferguson acknowledged his side were beaten by the better side and the defending champions must now focus on getting three points against Swansea.
“It’s been quite muted and a quiet place to be,” he added. “It’s to be expected when we lose a game like that. Our job is to get the players up for the game on Sunday because it’s such a big game for us.
“We have to analyse it [the derby] as it’s part of the game. Even when we win, it’s to see good and bad points and we’ve done all that. It’s over with.
“It’s not something we address with the players, it’s for the staff’s knowledge – myself, Mike [Phelan] and Rene [Meuelensteen]. It’s for our knowledge in terms of could we have done something different?
“At the end of the day, there were some fantastic footballers on that pitch and we didn’t do well enough.”
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