United earned a fifth successive win over Liverpool with a classic smash and grab raid at Anfield through Wayne Rooney's winner 12 minutes from time.
The Reds captain struck on 78 minutes to settle an evenly contested encounter, seal back to back league doubles over our North West neighbours and send United to within two points of fourth placed Spurs.
Liverpool had enjoyed most of the chances and much of the play over the 90 minutes, but United's excellent containment job led to the vintage breakaway winner
Adam Lallana went close for the hosts early on, when his header was blocked by the onrushing David de Gea, before Roberto Firmino dragged his follow-up inches wide with the goal gaping.
James Milner blasted over soon after before a coming-together between the feisty pair of Marouane Fellaini and Lucas saw tensions ignite and both players escape with merely a warning.
Jordan Henderson flashed a dipping drive narrowly over the bar and Anthony Martial's excellent lunging tackle thwarted Firmino after a rapid Liverpool break from a United corner.
David De Gea saved well with his legs to deny Emre Can five minutes after the interval, whilst Martial fired inches wide at the other end after excellent work from substitute Cameron Borthwick-Jackson.
The chance sparked encouragement in the away end, which featured injured trio Phil Jones, Michael Carrick and Marcos Rojo as their side gradually grew into the game.
Liverpool still continued to look most likely, though, as United were indebted to a brilliant double save from De Gea to keep out first Can and then Firmino from the follow-up.
By now, Louis van Gaal had introduced Memphis and last season's Anfield hero Juan Mata, and the boss was rewarded as his side soon began to take the upper hand in pursuit of a vintage counter-attacking victory.
After playing such a key role in this fixture last season, Mata will have been disappointed to find himself on the bench but the Spaniard was to turn provider this time around.
Daley Blind found Mata with a short corner and his cross picked out Fellaini whom nodded against the bar, but Rooney was there to blast in a volley into the top corner- the revitalised skipper's fifth goal in four games in 2016.
Having been hit with a late sucker-punch, Jurgen Klopp's side were unable to rally and United held out for an important and satisfying victory against our great rivals.
Overall team performance: 7/10
United Faithful Man of the Match: De Gea and Smalling deserve honourable mentions, but Morgan Schneiderlin gets our vote for him immense mopping up job.