Even the most optimistic of Manchester City fans may have accepted that the Premier League title was beyond them when Manchester United held a seven-point lead just weeks ago.
Now, though, Roberto Mancini's side have completed a remarkable turnaround, with their 1-0 victory over the Red Devils in the biggest Manchester derby in history putting them just two games away from winning a first league title since 1968.
On a nervous evening, Vincent Kompany's header just before half-time eventually proved decisive at Eastlands and the hosts now lead the standings on goal difference.
The fallout from the result is only just beginning and it remains to be seen who will have the last laugh in a season which is sure to produce more twists and turns as the two sides continue their battle for the title.
But as City fans begin their celebrations and supporters of United struggle to come to terms with what they have witnessed, Goal.com relives the key moments of a Manchester derby that will live long in the memory for one half of the city.
Fans arrive | A sell-out crowd filters into Eastlands as a global TV audience tunes in
Close to kick-off | The two managers appear to be relaxed in the moments before the game
Steady start | United begin looking brighter with City making a nervous opening
Poor show | Nani fails to make the most of some early openings
No love lost | The challenges start flying in, with Park making little impact on the game
Moving into gear | City begin to look more comfortable as the first half progresses
Barking orders | Mancini was more animated than usual on the touchline
Star power | Diego Maradona is spotted supporting City in the stands
Decisive moment | Kompany heads home Silva's corner on the stroke of half-time
Eastlands erupts | The home fans sense a famous victory
Disconsolate | United ponder falling behind as their gameplan unravels
Frustrated Fergie | Sir Alex looks on as his side are suddenly trailing
Hosts hold firm | United start the second half briskly without creating a clear chance
Game in the balance | Nasri & Aguero hook shots wide at the other end
No goalmouth action | The ball is not breaking for the forwards on either side
Tensions boil over | Fergie & Mancini square up on the touchline as tense game nears end
Isolated | Rooney sees little of the ball despite Welbeck, Young & Valencia coming on
Full time | The whistle is greeted with a huge roar as Kompany & Co. celebrate
Disappointment | United acknowledge away fans but now know the title is out of their hands
Ecstatic | Hart celebrates having had little to do during the 90 minutes
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