A much-changed United side were left to count the cost of missed chances as Liverpool came from behind to register a 3-1 win over the Reds in the Barclays Under-18 Premier League.
Ashley Fletcher gave United a first-half lead, latching onto a diagonal pass from Jordan Thompson ahead of Liverpool goalkeeper Ryan Crump before calmly nudging the ball into the untended goal, but both Nick Ioannou and Marcus Rashford spurned one-on-one openings before the hosts struck three times in the final half-hour.
A Jerome Sinclair penalty levelled matters and prompted a spell of dominance from Liverpool, who took the spoils when Alex O'Hanlon smashed a 25-yard effort past Reds goalkeeper Dean Henderson and Sinclair doubled his tally in injury-time.
Although several regulars were rested ahead of the Reds' must-win UEFA Youth League clash with Shakhtar Donetsk on Monday evening, a disciplined display from United kept the hosts at bay for the first half and, with better finishing, might have secured an unassailable lead.
Right-back Joe Riley almost burst through on goal in the 9th minute after a neat exchange with Fletcher, only for Crump to pip him to the ball, before Liverpool's Conor Randall managed to head off his own line under pressure from Marcus Rashford.
Though Neil Critchley's side enjoyed a fair share of possession, United forged ahead midway through the first period when Fletcher reached Thompson's ball before Crump and, despite O'Hanlon's presence, kept his composure to nudge United into the lead.
Liverpool looked to hit back quickly, but Reds stopper Henderson superbly turned Sergi Canos' effort away from goal and Ryan Kent's low effort rolled a yard wide of the upright.
United continued to defend stoutly, and should have doubled their lead shortly before the interval.