Silva netted his sixth league goal of the campaign with a clever close-range finish after 53 minutes, leaving Luke Shaw for dead before rifling low and hard into the bottom corner. David de Gea had little chance of saving that effort, but should have done better at his near post to deny substitute Leroy Sane's finish on a devastating counter-attack twelve minutes later.
The defeat is United's seventh in their last nine games, with Ole Gunnar Solskjaer's men struggling for both confidence and consistency as they pursue a Champions League place with three top-flight games remaining this term. With all of that in mind, here's a look at five talking points from another intriguing Manchester Derby:
#5 Lukaku and Sane in stark contrast from the subs' bench
United had a few notable surprises while City made three changes to the side that beat Tottenham 1-0 on Saturday. Even when you compare both benches, the attacking quality having to bide their time on the bench is remarkable. Leroy Sane, £60m man Riyad Mahrez and Gabriel Jesus vs Anthony Martial, £75m man Romelu Lukaku and an out-of-form Alexis Sanchez - still dangerous - to choose from for Solskjaer.
Sane came on after Fernandinho's knee injury in the 50th minute, but with United needing fresh attacking impetus after City's spirited display after the restart, Lukaku was tasked with helping steer an unlikely comeback with 20 minutes left.
Leroy was pivotal in the build-up to their first goal, albeit a brief warning sign before Silva's finish. A well-worked move saw him attempt to cut the ball across goal for Sergio Aguero - but the Argentine was denied by an important interception by Victor Lindelof.
It ultimately counted for little though, as City went and scored 35 seconds later, this time attacking the other side. Then it was he who doubled their lead with a powerful effort driven into de Gea's near post after Sterling teed him up on the counter-attack. Despite his best efforts, the Spaniard could only parry it into the bottom corner.
As for Lukaku, well, his presence didn't have a significant impact on the game. His evening's work was typified by a miscued shot that flew horribly wide of goal and in truth, it didn't help his case. He, alongside Pogba, was scapegoated for a number of United's shortcomings under Mourinho and hasn't really had a fair crack at the whip under Ole's current reign despite flashes of his ability.
The Belgian's match statistics speak for themselves: 18 touches, dispossessed five times, one tackle completed, one shot (off-target) and 57.1% pass accuracy - a game-low. Naturally the sample size isn't big because he only played 20 minutes, but you get the point. For someone so eager to impress, whether that be United or other interested suitors, he needs to do more to justify a starting berth - even if his teammates are struggling for form.