Mason Greenwood emulated a feat last achieved by Cristiano Ronaldo and Jesse Lingard's astonishing purple patch continued in another enthralling weekend of Premier League action.
Greenwood came off the bench to play a big part in second-placed United's 3-1 victory at Tottenham on Sunday.
Lingard also starred in London earlier in the day, scoring twice in a 3-2 win over Leicester City to keep West Ham on course to defy the odds and seal a Champions League spot.
Leeds United shocked champions-elect Manchester City 2-1 at the Etihad Stadium on Saturday, while Alexandre Lacazette brought up a half-century of goals in Arsenal's 3-0 success at rock-bottom Sheffield United.
Using Opta data, we look at some quirky facts from the latest Premier League matches.
Greenwood sets high sub standard
As cameo appearances go, Greenwood's short time on the field against Spurs was right up there.
The 19-year-old replaced Marcus Rashford after 72 minutes at Tottenham Hotspur Stadium with the game in the balance at 1-1.
Ole Gunnar Solskjaer could surely not have wished for a bigger impact from the forward, who laid on a goal for Edinson Cavani before sealing all three points by finding the back of the net himself deep into stoppage time.
Greenwood became the first teenager to score and assist as a substitute for United in a Premier League match since the legendary Ronaldo did so against Portsmouth in November 2003.
Lethal Lingard outfoxes Leicester
On the subject of big impacts, Lingard has been a revelation for the Hammers since his loan move from Manchester United in January.
The England forward can do no wrong at the moment and helped himself to a first-half double in a huge victory over the Foxes, moving David Moyes' men back up to fourth.
Lingard has now scored in four consecutive games for the high-flying London club, taking his tally in the Premier League to eight.
That equals his best goalscoring return in a top-flight campaign and he has only made nine appearances. Lingard also netted eight times for his parent club in the 2017-18, but that was from 33 matches.
Leeds claim rare win over leaders
Leeds have been a breath of fresh air on their long-awaited return to the Premier League and they claimed the scalp of City on Saturday.
A Stuart Dallas double consigned Pep Guardiola's side to only their fourth top-flight loss of the season, moving Leeds into 10th place.
The Whites are only the fourth promoted side to win away against the Premier League leaders in the competition's history.
Ipswich Town beat then-leaders Norwich City in December 1992, Derby County won at Manchester United in April 1997 and Hull City left Arsenal shellshocked with a win in the capital in September 2008.
Lacazette brings up his 50
Arsenal lifted the gloom with an emphatic win over Championship-bound Sheffield United, with Lacazette leading by example as captain.
The striker scored twice at Bramall Lane and now has 50 goals for the Gunners in the Premier League.
He is the sixth Frenchman to reach that landmark in the competition for a single club, with Thierry Henry, Olivier Giroud and Robert Pires three of those to have scored a half-century of goals for Arsenal.