Manchester United came from behind to wallop neighbours Manchester City 4-2 on Sunday, in a match which all but ends City’s hopes of defending their Premier League crown.

Sergio Agüero had given City an eighth minute lead to end a six-game goal drought, tapping in from close range after James Milner’s defence splitting pass set David Silva on his way to setting Agüero up from the near post.

The goal was the lift City needed, having come into the derby on the back of a disappointing 2-1 loss at Crystal Palace and a poor run of five defeats in their last seven matches in all competitions.

But Manuel Pellegrini’s side were up against an in-form United that had won their last five league matches and soon found themselves trailing no thanks to an unexpected source.

Ashley Young equalised after 14 minutes, reacting quickest to score into the roof of Joe Hart’s goal after his initial effort was blocked, with the ball bouncing off his back to set him up for the finish from four yards.

A spell of dominance by City was then quelled in the 27th minute when Young turned provider for Marouane Fellaini who, marginally onside, headed past Hart to turn the tie in United’s favour.

Rooney saw a free-kick saved by Hart early in the second period while Young miscued a header wide when found unmarked in the City area, though he was flagged offside.

Nonetheless, United’s hold on the game was stamped after 67 minutes when Mata was found offside by a Rooney pass before slotting through Hart’s legs to give United a 3-1 lead.

Poor defending from Eliaquim Mangala – who replaced injured captain Vincent Kompany at half-time – allowed Chris Smalling to be played onside and head in a Young cross unmarked after 73 minutes.

The Red Devils were reduced to 10 men late on when Michael Carrick went off injured after United had made their three substitutions; having sent summer signings Marcos Rojo, Angel di Maria along with winter signing Radamel Falcao on in the course of the second half.

City made some use of the man advantage on the dot of the 90, with Samir Nasri and substitute Frank Lampard combining to set up Agüero for his second of the evening and 100th goal for City in all competitions.

The goal however was too little too late for City, as United ran out 4-2 winners to maintain third spot on the league standings and open a four-point gap on their fourth placed city rivals ahead of what could be a title decider at Chelsea on Saturday.

For City, it is now six losses in their last eight matches and the outlook getting dimmer by the day for manager Pellegrini; to whom United fans sang ”You’re getting sacked in the morning” to.

It may not come in the morning but it does seem inevitable now for Pellegrini.