Erik ten Hag was reunited with a manager he knows well from the Netherlands, new Liverpool boss Arne Slot.
Is is the 'new manager bounce' or is Arne Slot simply a more effective tactician and manager than Erik ten Hag?
The new Liverpool manager coached his team to a 3-0 victory at Old Trafford, which United fans feared mid-game could get even more embarrassing.
In just his third Premier League game, Slot beat Ten Hag. It's not a good look, with United already suffering a second defeat of the season.
Yet it must also be remembered, for those trying to bury the under-fire United manager, that in Ten Hag's third United game, he beat Jurgen Klopp.
Dutch outlet FCUpdate ran a headline, 'Slot humiliates Ten Hag: Liverpool is far too strong for Manchester United'
Their report noted that United started well yet could not create clear cut chances, before individual errors turned the course of the game.
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Volskrant reported: "Arne Slot has put fellow coach Erik ten Hag in a difficult situation early in the season."
The report added: "Where the former Feyenoord coach could not suppress a laugh, Erik ten Hag looked worriedly at the lousy football of his players. What the Mancunians showed in this classic was pitiful."
It signed off with: "Where Slot walks across the Mersey, Ten Hag must fear for his immediate future after two defeats in three games."
Het Parool added that Liverpool were simply 'too strong' and 'Ten Hag can expect a lot of criticism in the coming days'.
Ten Hag's overall record vs Arne Slot Erik ten Hag had faced Arne Slot previously with Ajax in the Netherlands up against Feyenoord.
His record there was four games played, two wins, two losses. Arne Slot now has the edge with three victories.
Manchester United face Liverpool at Anfield in the opening game of 2025.
Will Erik ten Hag still be in charge by that fixture? It's a topic which will dominate conversation over coming months, unless Manchester United's form can pick up.