Fulham’s Under-18s were punished by a resilient Manchester United despite putting their opponents under heavy pressure throughout at the Trafford Training Centre.
Sam Byrne's 20th-minute strike put United ahead and the striker doubled his tally on 26. However, Pat Roberts' sixth goal of the season on the stroke of half-time brought the Whites back into the game.
It was a lifeline the young Whites fully deserved after more than matching their opponents in the first 45 minutes but, despite controlling long periods of the second half, United hung on and James Wilson hit a late third against the run of play.
United snatched a 20th-minute lead when the dynamic Liam Grimshaw twisted and turned through the Whites midfield and delivered an inviting cross which Joe Rothwell met with a powerful header.
Goalkeeper Marek Rodak launched himself across goal to block the initial attempt but Byrne reacted quickest to the loose ball and tucked the Red Devils into the lead.
The hosts soon doubled their advantage when Jack Barmby robbed Josh Passley in a dangerous position and the son of former England international Nick played in Byrne to stroke in his second.
Steve Wigley's side almost offered the best possible response on the half hour when Liam Donnelly was allowed a free header from George Williams' inswinging corner but his effort flew wide of United's post.
Fulham's strike partnership were combining well and when Muamar Tankovic slipped Moussa Dembele in behind United's backline, goalkeeper Pierluigi Gollini was called upon to deny the Whites the route back into the game which their play deserved.
There were more near misses as Tankovic's dipping free-kick stung the hands of Gollini and from the resulting corner, Dembele jumped highest but his header was finger-tipped over by United's stopper.
But the Whites' lifeline finally arrived in first-half stoppage time when Williams set off on a marauding run past James Weir and Byrne before showing excellent composure to cut back for Roberts to add the finish.
Picking up in the second half where they left off, the Whites continued to force United onto the back foot, with Emerson Hyndman forcing Gollini into a stretching save and Donnelly heading over from close range.
With the clock ticking down, Fulham continued to pour forward but Tankovic's free-kick failed to trouble Gollini and Donnelly's late effort was hacked off the line.
Then the Whites frustrations were compounded as the home side counter-attacked in stoppage time and substitute Wilson was on the mark to wrap up United's win.
Fulham: Rodak, Donnelly, Burgess, Richards, Passley; Roberts, Sambou, Hyndman, Williams; Tankovic, Dembele.