United's Under 23s recorded a derby victory over Sheffield Wednesday at Hillsborough thanks to first half goals from Paul Coutts, Oliver Greaves and Martin Cranie.
With Coutts, Cranie and Daniel Lafferty once again all starting, it was a strong Blades line-up but it was the hosts who enjoyed the best of the exchanges, testing Eastwood several times in the opening 15 minutes.
The game turned in United's favour with 18 minutes gone when Joe West brought Harry Sheppeard down inside the box, allowing captain Coutts the chance to step up and smash his penalty into the top left-hand corner of the net.
United rarely looked back after that and as soon as it was one it was two. A neat move saw Jordan Hallam beat the goalkeeper to a ball and his pull-back left Greaves with the task of slotting home into an empty net to make it 2-0 inside 25 minutes.
With just over five minutes to go until the break United added a third. Hallam was once again the provider as Cranie rose highest to head the forward's corner into the corner of the Wednesday net.
The hosts did pull a goal back just before the break when Liam Waldock slid the ball home from Jack Stobbs' through ball and set up a potentially tense second half.
But United played out the second half in a calm manner and despite a couple of chances for the hosts, Jake Eastwood was rarely tested during the second 45 minutes of the entertaining encounter.
United could have added some further gloss to the score line themselves when nobody managed to connect with Sheppeard's pull back, before the winger himself headed just wide from close range after McCulloch had pushed away Hallam's curling effort.
Despite Wednesday trying to apply some late pressure, United saw out the remaining minutes without drama to seal a deserved victory against their city rivals.
Blades: Eastwood, Cranie, Bennett, Coutts, Cantrill, Doherty, Sheppeard (Boyes 78), Greaves (Oure 90), York (Parkhouse 86), Hallam, Lafferty.
Unused: Gordon, Dewhurst.