The Red Devils were rampant. It feels like a throwback statement, but then this was something of a throwback game as, for the first Premier League meeting between Manchester United and Leeds United since 2004 and the return of one of the great fixtures of British football, they rolled back the years.
Beyond being a gloriously bonkers match, what does it mean? United are back in a top four, with a game in hand, which is almost as unpredictable as this relentless encounter.
Leeds conceded half a dozen goals and it could have been a lot more, but they also scored two and made some glaring misses. Both goalkeepers played well. There were 43 shots and yet the man of the match was Scott McTominay, a defensively minded midfielder.
The game was incredibly open as Ole Gunnar Solskjaer celebrated his two years as United manager with the most goals they have scored in the league since beating Arsenal 8-2 in 2011. He became the first coach in 28 years to inflict six goals on Marcelo Bielsa. The last time that happened he was coaching in Argentina.
Can United even be title challengers? It seems unlikely, but this is a crazy campaign and, maybe, this formula of playing with more attacking intent might serve them well even against defensively stronger teams than Leeds who, as entertaining as they are under Bielsa, are haemorrhaging goals. As much as Leeds fans are enjoying their return to the top flight, and the football they play, losing like this to United has to hurt.
Leeds conceded four in the first half - two in the first 170 seconds - with both coming from an unlikely source: McTominay. They made him the first player in Premier League history to score twice in the first three minutes of a game.
Where has this version of McTominay been hiding? Or did Leeds's naivety bring about the transformation? Both goals were exceptional finishes, although, as with all their concessions, Leeds played a significant part in their own undoing.
For the first, Rodrigo lost the ball and Bruno Fernandes was allowed to stride forward and square to McTominay, who struck a superb first-time shot from the edge of the penalty area that swerved away from Illan Meslier.
For the second, there was a throw-in and Anthony Martial ran across the face of the area, before slipping a pass to McTominay. With Mateusz Klich failing to track his run, McTominay deftly controlled the ball and beat Meslier with a low shot back across the goalkeeper.
Leeds will always threaten - and United will always give up chances - and Patrick Bamford should have halved the deficit when he was put clear by Rodrigo, catching out Victor Lindelof, only to side-foot wide.
Would that have made a difference?
Instead, United scored two more goals. Once more Rodrigo lost the ball with a slack pass that was intercepted by Daniel James - making a surprise start against the club who tried to buy him before he moved to Old Trafford - and United broke as Fred picked out Martial. Luke Ayling poked the ball away, but only to Fernandes, who drove another powerful first-time shot to beat Meslier.
The same frail template applied as Bamford lost the ball and a corner was eventually conceded. Luke Shaw's kick was flicked on by Martial - with neither Bamford nor Stuart Dallas reacting - and Lindelof stole in at the far post to side-foot home as Kalvin Phillips failed to track him. It was also yet another set-piece goal conceded by Leeds.
But neither do Leeds give up and, before half-time, Raphinha's corner was met by Liam Cooper, who steered his header goalward. David de Gea got a hand to it but could not keep it out, although the bigger issue - literally - for United was why a 6ft 2in centre-half was being marked by Fred, a 5ft 7in midfielder.
Even though it was 4-1, it did not feel over and, after Martial curled a shot narrowly wide, De Gea made a stunning save to deny Raphinha after he volleyed Rodrigo's cross. Soon after, De Gea denied Raphinha with a smart low save.
Just as Leeds pushed on, United struck as McTominay broke forward, held off Rodrigo and picked out James, whose first touch took him past Ayling and in on goal, before he shot between Meslier's legs. It was the winger's first league goal since August 2019.
United scored another, this time from the penalty spot, after Martial was caught by substitute Pascal Struijk. Fernandes stroked the ball past Meslier.
It was Fernandes's last act as he and Marcus Rashford were taken off, before Leeds claimed what was to be the last goal, but certainly not the last chance. Raphinha cushioned the ball into the path of Dallas, who took a touch, before bending a shot from 25 yards around De Gea and high into the goal.
Meslier made a string of fine saves: he denied Martial with an outstretched leg, repelled an effort by substitute Edinson Cavani and James's follow-up, beat out a cross-shot from Alex Telles, another replacement, and excelled in denying Fred, who was almost as impressive as McTominay.
Even then, there was still time for a glaring miss as the unmarked Jack Harrison side-footed wide.
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