Vincent Kompany’s thunderous header on the stroke of half-time was all that separated the two sides in what was a cagey affair at the Etihad Stadium.
The Reds Devils failed to conjure a single shot on target as Joe Hart enjoyed a relatively straight forward assignment, while City managed to test De Gea on three occasions.
“They [United] wanted to take a draw,” said Mancini.
“I think this is the difference. We wanted to win, we had the chances and we played better.”
The result hoists City above their local rivals on goal difference with two games left to play – but Mancini refused to get carried away with the victory with a difficult trip to Newcastle and a home clash with QPR still to come.
Ferguson’s side face Swansea City at Old Trafford this weekend before making taking on Martin O’Neill’s Sunderland at the Stadium of Light.
“It was an important result,” added Mancini. “I think now we have a chance [to win the title] in our hands. But I’m not happy only for me but for our supporters.
“We can talk about everything now but we need to play another two games that we want to win.”
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