Jordy Hiwula had given City the lead after 16 minutes with a tap-in after great work from Devante Cole, before James Wilson levelled the score for Warren Joyce’s Reds with the final kick of the first half.
Wilson went on to hit three more in a dominant second half for United, meaning that United lifted the Robinson’s Brewery trophy for the fourth successive year.
City had reached the final by defeating Oldham and Rochdale in the group stages, with the latter match holding special significance to Patrick Vieira and his charges.
A penalty shootout win over Rochdale in October 2013 kicked-off a stunning 13-game unbeaten run for the Elite Development Squad, which saw them qualify for the end of season league play-offs and the final of the Premier League Cup.
Vieira would have hoped that victory over a familiar foe and a first piece of silverware in management would fuel a similar run with the Barclays u21 Premier League getting under way away at Chelsea a week on Friday.
Rumours that Manuel Pellegrini would field a selection of his returning World Cup stars which had circulated on social media in the build-up to the game proved to be well wide of the mark, as the EDS boss picked a familiar-looking young side for the night’s game.
The Frenchman opted to keep faith with the central defensive partnership he’s fielded for most of pre-season, teaming up Kean Bryan and Pablo Maffeo, with Angelino and Mathias Bossaerts on either side in the full-back berths in front of Angus Gunn.
George Glendon, scorer of the winning goal last time these teams met in January, wore the captain’s armband at the base of a midfield three alongside Parisian duo, Seko Fofana and Olivier Ntcham.
2012/13 top-scorer Jose Angel Pozo started his first competitive game since recovering from the ankle injury which kept him out for the most part of the previous campaign.
The Spanish youth international started on the left of an attacking trident, with Cole starting on the right and the in-form Hiwula in the central no.9 role.
There was a pre-season feel about the opening quarter of an hour with City stroking the ball from back to front and back again to work the opposition around but Vieira’s men were ahead after 16 minutes, much to the delight of the majority inside Ewen Fields.
Cole broke down the left flank and took the United goalkeeper out of the game with a measured cross-cum-shot across the face of goal, leaving last season’s top scorer Hiwula with the simple task of tapping the ball into the empty net.
Technically, it was Jordy’s 20th goal of the 2013/14 season – even though the 2014/15 season starts in eight days!
A second goal nearly followed from the same left wing source after some mesmerising footwork from Fofana a few minutes later but, when Seko fed Cole, this time his cross was snuffed out by the United back four before it found Hiwula.
A lengthy drinks break, taken when Bryan took a heavy fall, robbed the game of some of its cadence until the final minute of additional time at the end of the half when United found an equaliser out of nothing.
James Wilson, who has played and scored for the first-team at Old Trafford, wriggled into the area down the right and finished off a nice solo goal with a thumping finish under Gunn.
Five minutes after the restart, Wilson had turned the game around, breaking clear before stabbing the ball past the onrushing keeper.
Twice City had switched off and they were duly punished by the clinical United no.9.
He would have completed a 15 minute hat-trick had it not been for the quick thinking Gunn, who raced off his line, spread himself and blocked Wilson’s goalbound slot.
Vieira’s side were holding on against their more physically developed opposition and it looked like curtains when Wilson did complete his hat-trick with another confident sidefoot to make it 3-1.
Thierry Ambrose was introduced from the bench to try and salvage the match but United scored a fourth through the rampant Wilson with eight minutes to go to secure the silverware.