Josh Harrop introduced himself to Old Trafford in some style as the debutant's stunning strike set the youngest Manchester United team in Premier League history on course for victory against Crystal Palace.
With Wednesday's make-or-break Europa League final against Ajax looming large, Jose Mourinho stuck to his word by resting numerous key players and handing four young prospects their full debut with sixth place already assured.
United's performance belied the starting line-up's tender average age of 22 years 284 days, with Harrop marking his first appearance with a superb effort that kicked off a surprisingly comfortable 2-0 win against Palace.
Paul Pogba superbly set up the 21-year-old's memorable 15th-minute strike and quickly added to it, firing home and pointing to the sky after missing the previous two games following his father's death.
Pogba and Jesse Lingard were withdrawn before half-time with an eye on the Europa League final, but captain Wayne Rooney played all but two minutes despite Mourinho strongly suggesting he would be rested.
On an afternoon that some suggested could be his final competitive United appearance at Old Trafford, the 31-year-old received a standing ovation as he was replaced by 16-year-old Angel Gomes - the first Premier League player to have been born in the 21st century.
There was precious little time for the England youth international to make a telling impact, but his appearance complemented promising full debuts by Joel Pereira, Scott McTominay, Demetri Mitchell and Harrop.
The quartet performed impressively on what could have been a long afternoon for much-changed United given Palace boss Sam Allardyce ignored Mourinho's plea to go "slow" with a strong line-up at Old Trafford.
Given the millions in prize money up for grabs that was little surprise, yet the way the hosts' callow side bossed much of the game did.
Youthful exuberance combined impressively with the more wily members of the starting line-up, epitomised by the fine raking pass by Mitchell that was met by Rooney and clipped just over.
United's full debutants looked unfazed, with one taking their chance superbly in the 15th minute.
Pogba played an outstanding ball with the outside of his boot to Harrop. Rather than picking an easy pass to Rooney, the unflustered 21-year-old showed quick feet and confidence to make space and fire home superbly.
Harrop became the 100th different player to score a Premier League goal for United and was soon joined on the scoresheet by another academy graduate, albeit this one was far better known.
Lingard burst through the middle and played through Pogba, who capitalised on Joel Ward slipping under pressure to slot through Wayne Hennessey's legs in the 19th minute.
It was the kind of cutting edge Mourinho will have wished his side had displayed earlier in the season, with Harrop curling just wide as Palace struggled to breakdown the hosts' young defence.
Allardyce's men failed to muster a shot on target during a one-sided half that took on an exhibition feel towards the end, with Pogba and Lingard replaced by Michael Carrick and Anthony Martial before half-time.
Another change was imminent early in the second half as Eric Bailly looked set to be forced off through injury, only for Matty Willock, stood on the touchlines, to be denied a United debut as the defender told Mourinho he was fine.
United's defence was soon breathing a sigh of relief as former United winger Wilfried Zaha sent in a cross met by a superb Christian Benteke header struck the base of the post.
After that, though, both sides were largely going through the motions, although Rooney nearly injected intrigue when directing a free-kick just wide of his own goal before Pereira did brilliantly to not only stop a Luka Milivojevic free-kick but hold onto it.
Play was now slow and stretched at Old Trafford, which witnessed history in the 88th minute as Rooney was withdrawn and replaced by debutant Gomes.
The United captain's name echoed around the ground as he received a standing ovation, replaced by the first player born in 2000 to feature in a Premier League match - and the youngest to have represented United in the competition.