Year-after-year current leaders Manchester United are praised for pulling results out of the fire on their way to yet another domestic success. So when chasing a title themselves, City deserve to be acclaimed to the heavens when they replicate such a feat.
Not only was their performance failing to inspire, but recent history suggested Mancini's men were facing an uphill struggle. City hadn't claimed a single point from a losing position in the Premier League this season.
With quality and finesse lacking, City employed desire and spirit for the closing stages, and got the break they deserved when Michael Essien handled, with Sergio Aguero subsequently sending Petr Cech the wrong way.
Among City's desperate attempts to grab a winner came the bit of cutting edge that eventually separated the two sides. Carlos Tevez slide-rule pass found Samir Nasri, who poked into the corner.
It was an apt climax to a City performance that, while it was devoid of effervescent attacking play onlookers were treated to earlier in the season, brought out the gritty side of Aguero, Nasri and Co.
If anyone had doubts of City's ability to win ugly, they were banished in one fell swoop. Forget the battering at White Hart Lane, or the crushing of United at Old Trafford, edging past Chelsea could prove to just as crucial in their title pursuit. The title run-in makes no room for style, substance rules when trophies are concerned.
Sir Alex Ferguson has made a career out of seeing out domestic titles, and City's performance would surely have struck a cord with the United boss.
Their result is even more impressive given the absence of both Vincent Kompany, often the common denominator concerning quelling shaky defensive displays, and Lescott, an underrated member of Mancini's title chasers.
For the neutral, the victory allows us to enjoy what is likely to be as thrilling a title run-in as any in the Premier League era. Just a point separates the two with nine still to play, six of which come before the summit meeting between the pair in late April.