City leapfrogged Chelsea into third place in the Barclays Premier League with their emphatic home victory over the Black Cats. It made for an interesting Sunday afternoon's entertainment for Manchester United manager Ferguson, who viewed the game from the stands at Eastlands ahead of his side's cup showdown with City at Wembley on April 16.
But asked if he thought Ferguson might be concerned by what he had witnessed, Mancini said: "I don't think so. He knows the FA Cup semi-final is one game in which anything can happen, and I think he knows Manchester City very well - like we know Manchester United."
Adam Johnson, making his first start since injuring his ankle in January, opened the scoring in the ninth minute and captain Carlos Tevez doubled the Blues' advantage on the quarter-hour mark from the penalty spot.
Second-half strikes from David Silva, Patrick Vieira and Yaya Toure completed the rout as City moved a point above Chelsea. They are also now six points ahead of fifth-placed Tottenham in the race for Champions League football, although both Spurs and Chelsea have a game in hand.
Mancini has frequently drawn criticism for his side's apparent conservatism, but with Tevez fit again having missed City's 2-0 defeat at Stamford Bridge with a groin problem, the manager opted to pair his top-scorer with Mario Balotelli up front.
Additionally boosted by the return of Johnson, it was a positive-looking team selection by Mancini which paid off even more handsomely than he expected.
"It was important for us to win this game because we had the chance to go into third position," the City boss said. "Before the game I thought it would be difficult because it is not easy to beat Sunderland.
"They are a strong team who work very well and their manager knows everything. But we started the game brightly and that was important. I am surprised but I am happy. It is important that we scored five goals.
"It is possible (that it will give us confidence for our remaining games), but it is important now that we continue and go to Liverpool looking to win next Monday."
Source: PA
Source: PA