Manchester, England (SportsNetwork.com) - Manchester United scored four unanswered goals after falling behind early to roll to a 4-2 win over Manchester City at Old Trafford on Sunday.

City entered the contest having won the last four Manchester derbies, and the visitors couldn't have asked for a better start as Sergio Aguero scored just eight minutes in to put City up 1-0.

However, goals from Ashley Young and Marouane Fellaini had United in front 2-1 at halftime before Juan Mata and Chris Smalling scored seven minutes apart after the break to hand United a massive three points, with Aguero scoring a late consolation tally to reduce the damage.

The result moves Louis van Gaal's men four points clear of City in third place and keeps the side one point behind second-place Arsenal.

Aguero has a history of success against United and he continued that early on Sunday as David Silva was played into the area on the left and squared the ball into the six-yard box for Aguero to turn home, giving the Argentina international seven goals in eight games against United.

But after City controlled the opening 10 minutes, United turned the game on its head and Young equalized in the 14th when a cross from Ander Herrera took a fortunate deflection that allowed the United man to score from close range.

Young turned provider in the 27th minute to put the hosts in front when his chip picked out an open Fellaini at the back post for a simple headed finish.

City goalkeeper Joe Hart made a nice save on Wayne Rooney's free kick and an even better one to deny Michael Carrick's rebound effort early in the second half.

However, United kept pressing and Mata made it 3-1 as he squeezed the ball between the legs of Hart after being played in on goal by Rooney.

Young had a hand in United's fourth goal as well when he curled a free kick to the top of the six-yard box that found an open Smalling, whose glancing header left Hart with no chance.

Aguero scored in the 89th minute from Pablo Zabaleta's pass, but it was little consolation for a City side that must now look over its shoulder at teams like Southampton and Liverpool in order to keep hold of a spot in the top four.

Sunday's other fixture saw Chelsea move seven points clear at the top of the league with a 1-0 win at QPR.

The relegation-battling side held Chelsea out for 87 minutes, but Cesc Fabregas scored on a first-time shot from Eden Hazard's pass to help the Blues move a step closer to the title.