City players celebrate following the winning goal
What can only be described as an imperious home form continued tonight with City sinking Chelsea's resurfacing submarine 2-1 at the Etihad.
The have now won their last 20 premier league home games—a new league record—but they didn't have it all their own way.
Mancini's side needed to come from a goal behind to prevent slipping further away from league leaders United, who were four points clear before kickoff.
The result proves that City are still very much capable of winning the title, and here's why.
City go 1-0 down to a deflected Cahill volley
Coming from behind against any team is no mean feet, but against a newly invigorated side under fresh leadership is even harder.
Chelsea have performed admirably since the departure of André Villas Boas, and now look far more organised and defensively sound.
City kept their cool throughout though and plugged away at the Blues' defence.
With nearly 60 percent possession and a whopping 14 shots on goal (to Chelsea's four), Mancini's men proved their resilience in overturning the deficit, a trait that is key in any title contender.
Samir Nasri chips it over Cech for the winning goal
It was a solid and hard-fought, if unremarkable, performance from the Citizens tonight.
But as well as grafting their way to victory, City required a collectively cool head, and that's what the players delivered.
Calm and composed throughout—as if they knew their chance would come—Nasri's deft finish for the winner was a fitting finale.
Very few passes went astray all night, and their build-up was measured and deliberate.
Aguero equalises from the penalty spot
As if it even needs mentioning, City's squad has a strength in depth that other top European sides can only marvel at in jealousy.
This was demonstrated again against Chelsea, as Mancini made three changes from the side that lost to Swansea in their last league outing.
When you can leave players like Edin Dzeko, James Milner and Gareth Barry on the subs bench, you know your squad is incredibly strong.
The main surprise though was the inclusion of Carlos Tevez amongst the substitutes, who came on to make a telling impact (more on that later).
Mancini has more than proved his coaching abilities this season, opting to switch from the more defensive style he championed last season to the more offensive one favoured this campaign.
His decision to bring Gareth Barry on for Mario Balotelli at halftime seemed bizarre at first, but he shored up the midfield, and when De Jong was withdrawn, he allowed the attacking players to push forward.
He is adept at reacting to the situation at hand, and his tactical nous has won and will continue to win City games in the league run-in.
Yes, that is right: The trouble-making, dissenting Argentinian, who has spent the past six months sunning himself in Buenos Aires, is back!
And it was a triumphant return for Tevez, setting up the winning goal and supplying a pacey, dynamic injection that City needed.
His comeback will give fellow strikers Balotelli and Dzeko a kick up the back side (if one was needed), and he will prove key in the run in for City.