Despite Manchester City's victory over United on Monday, which took them back to the top of the table on goal difference with just two matches remaining, Mancini continues to regard his team as underdogs. His theory is that United have an easier run-in, which in some senses is correct given City must travel to face in-form Newcastle on Sunday.
However, Ferguson said: "They have got two games left. If they win their two games they win the league. People talk about goal difference, but it depends how many they win by. Say they win 3-0 on Sunday, their lead would be 11 and they still have QPR at home. That would be impossible."
Having seen an eight-point advantage slip through his side's fingers in the space of four games, Ferguson can only hope Alan Pardew's Champions League chasers do United a massive favour in a game that ends only half an hour before the Red Devils take on Swansea at Old Trafford.
"The challenge for City is to win at Newcastle," said Ferguson.
"Newcastle is a very difficult place and they are playing well. After that incredible defeat at Wigan, they galvanised themselves to win at Chelsea and, as everyone knows, winning at Chelsea is very difficult. We have not done it for eight years."
Danny Welbeck and Jonny Evans have both been ruled out for Swansea's first visit to Old Trafford since 1983.
The Welsh outfit have never beaten United away from home but Ferguson has seen enough of Brendan Rodgers' side this season to know it will not be easy, as Mancini has claimed about United's entire run-in.
"We don't have easy games," said Ferguson. "If you go to Sunderland on the last day of the season, with the support they have and the manager they have got, you don't expect an easy game, and the way Swansea have played this season has been admirable.
"Their manager has stuck by his principles and they have had a fantastic season."
Source: PA
Source: PA