Carlos Tevez’s 59th-minute winner inflicted Chelsea’s first defeat of the season, allowing Mancini’s men to narrow the gap at the top of the table to four points.
However the former Inter Milan boss still believes Carlo Ancelotti’s team are favourites to win the Premier League title this season.
“I still think they will win it easily because I think they are the best team in the Premier League,” said Mancini.
“It is not possible for them to score five goals every game. Sometimes you might get a result like this. But they are the better team.”
Chelsea struggled to breakdown a resilient City defence, with the visitors restricted to long-range efforts as the reigning champions sought to level the match. Mancini paid testament to the performance of his defenders, notably Vincent Kompany and Dedryck Boyata.
“If Chelsea find space it is east for them to score but if they don’t have space it is too hard and our players defended very well,” noted the 45-year-old.
Tevez also received praise from Mancini for his battling qualities, whose excellent display was in stark contrast to the unusually quiet Didier Drogba and Nicolas Anelka.
“Carlos is a fantastic striker,” said Mancini. “Not only because he scored but because he fights all the time against tall players.
“At this moment we don’t have all our players, so for him to be on his own is not easy for him.”
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