The 195th Manchester derby was an intriguing watch but not a scintillating one for the Etihad crowd. A frantic start to the first 45 and a fiery flashpoint between Rasmus Hojlund and Kyle Walker livened things up, but both sides struggled to test their opposing goalkeepers.
One of only three recognised defenders in Pep Guardiola's lineup, Josko Gvardiol was the man who broke the deadlock with a towering header nine minutes before the interval - his fourth Premier League goal of the season.
There appeared to be no signs of a Man United fightback; opportunities were at a premium and Ruben Amorim's side were frustratingly wasteful with the few chances they were presented with, none more so than Bruno Fernandes who dinked a shot narrowly wide after bursting through on goal.
However, the Red Devils turned the contest on its head in remarkable fashion, with Fernandes's confident penalty - one gifted by Portuguese compatriot Matheus Nunes who clumsily fouled Amad Diallo - followed by a majestic 90th-minute match-winner from Diallo, sparking pandemonium in the away end and boos from the home crowd.
Defeat for reigning champions Man City leaves them sitting fifth in the Premier League table and crucially nine points behind leaders Liverpool, who have a game in hand, while Man United have climbed up one place to 12th and are six points behind the top four.
SPORTS MOLE'S VERDICT
Oliver Thomas live from the Etihad Stadium:
A cagey contest lacking goalmouth action was perhaps symptomatic of two out-of-form teams who fully understood the importance of this derby showdown.
Man City entered this fixture on the back of a disappointing 2-0 defeat to Juventus in the Champions League just four days ago, and they looked on course to return to winning ways against Man United. However, what transpired in the dying embers was nothing short of remarkable - City collapsed on home soil again having previously let a three-goal lead slip in a 3-3 draw with Feyenoord last month.
Operating as a hybrid left-back, Nunes endured a forgettable afternoon as his horrendous mistake and clumsy foul on Diallo was punished by Fernandes from the penalty spot, and City's defensive frailties were exposed once again just two minutes later when Diallo raced through and snatched victory with a smart finish.
Those who were still questioning whether this injury-hit Man City side were in crisis can think again; one win, two draws and eight defeats have been posted across 11 games by a Guardiola side that looks unrecognisable, and one that have a fight on their hands to secure a top-four finish, not the title.
As for Man United, Amorim's bravery to leave out Marcus Rashford and Alejandro Garancho ultimately had the desired impact - albeit late on - as Fernandes and Diallo delivered on the big occasion to help the Red Devils return to winning ways in the Premier League in satisfying fashion, having previously suffered losses to Arsenal and Nottingham Forest.
Man United were by no means perfect at the Etihad, but their never-say-die attitude in the closing stages punished a mentally frail Man City team, who arguably have as many problems as Amorim's side to resolve in the coming weeks and months if they wish to end the 2024-25 campaign on a high.
MAN CITY VS. MAN UNITED HIGHLIGHTS
Josko Gvardiol goal vs. Man United (36th min, Man City 1-0 Man United)
A recycled corner fell to Kevin De Bruyne on the left and his deflected delivery was met on the edge of the six-yard box by Josko Gvardiol, who powered a towering header into the top-left corner, beating Andre Onana all ends up.
Bruno Fernandes goal vs. Man City (88th min, Man City 1-1 Man United)
Matheus Nunes's poor backpass towards Ederson was pounced upon by Diallo. He then waited for Nunes to come charging in to arrest his mistake and was barged to the floor by Man City's No.26. The Etihad was stunned and Fernandes slotted the resulting penalty kick into the right side of the net, sending Ederson the wrong way.
Amad Diallo goal vs. Man City (90th min, Man City 1-2 Man United)
Man City had no time to reset and Man United capitalised on that in devastating fashion. Lisandro Martinez's pass over the top of the hosts' defence was met brilliantly by Diallo, who tapped the ball over Ederson before somehow slotting a smart finish through the legs of Gvardiol on the line from a tight angle.
MAN OF THE MATCH - AMAD DIALLO
In a closely-fought contest with few standout performers, Amad Diallo was Man United shining light. Having operated mostly as a wing-back in the early stages of Amorim's reign, Diallo excelled in an advanced role against Man City, and it was the Ivorian who won the Red Devils' penalty before netting a composed winner in impressive fashion.
The 22-year-old, who is the second-youngest player to score a 90th-minute winner against the reigning Premier League champions after Neil Mellor versus Arsenal in 2004, completed five of his eight dribbles, 94% of his passes and contributed defensively with seven ground duels.
MAN CITY VS. MAN UNITED MATCH STATS
Possession: Man City 52%-48% Man United
Shots: Man City 10-10 Man United
Shots on target: Man City 3-3 Man United
Corners: Man City 8-2 Man United
Fouls: Man City 5-14 Man United
BEST STATS
WHAT NEXT?
Man City now have six days to prepare for their final Premier League game before Christmas away against Aston Villa on Saturday lunchtime.
As for Man United, they will turn their attention to next Thursday's EFL Cup quarter-final clash with Tottenham Hotspur in North London.
Written by
Oliver Thomas