By Chris Davie
Even before Edin Dzeko had raced onto David Silva's sublime pass and slotted past David de Gea to condemn Manchester United to their heaviest Premier League defeat in history, questions were inevitable after City's resounding display against the champions.
Before the match had started, Roberto Mancini was under scrutiny regarding his team selection - largely surrounding the inclusion of Eastlands extrovert Mario Balotelli.
It was the Italian, however, who first influenced as his cool, side-footed finish from outside of the area hushed United's initial attacking onslaught and resulted in arguably the best celebration in Premier League history as his firework antics were greeted with a lift of the jersey to reveal a simple question - 'Why always me?'.
But the influence of Balotelli, who notched City's second 15 minutes after Jonny Evans was dismissed following his last-man tug on the forward, was just one of the many decisive factors regarding City's rout at Old Trafford.
The red card justifiably awarded to the Northern Ireland international enabled City's attacking trio of Balotelli, Aguero and David Silva to run rampant - but wast it decisive?
Despite Darren Fletcher's fine strike nine minutes from time, United always looked stretched and nervy - Mancini's side had all the hallmarks of a side capable of controlling a game with a man advantage.
Was Sir Alex Ferguson's team selection to blame? The in-form Phil Jones was left on the bench, Javier Hernandez too was among the substitutes in favour of Danny Welbeck in attack. Park Ji-Sung also missed out, despite owning a wealth of big-game experience during his time at United and the Red Devils were outnumbered in the midfield area by sticking with a 4-4-2.
But any selection foibles from Ferguson should not take away the strength of City's performance, which again was inspired by a David Silva masterclass in ball control and incisive passing and makes for a strong statement regarding a Premier League title challenge. Were City simply too good on the day?
Or perhaps, if you're a die-hard United fan, you would be wiling to attribute City's result, which now sends them five points clear of Ferguson's side, to pure bad luck on the part of the hosts?
What was the main reason for City's emphatic victory? Have your say below by voting in our poll and leaving a comment - keep an eye out for the results in the days ahead.