Manchester United manager Erik ten Hag was booed by his own fans during the Red Devils' 3-1 loss at home to Brighton in the Premier League on Saturday.
The Seagulls took the lead in the first half through former United striker Danny Welbeck and went in ahead at the break.
United thought they had levelled through summer signing Rasmus Hojlund after 41 minutes, but the ball was adjudged to have gone out of play in the build-up and the Dane's effort was ruled out by VAR.
Brighton then went two up through Pascal Gross eight minutes into the second half and even though he had looked like United's main goal threat, Hojlund was replaced by Anthony Martial with almost a third of the match still to play.
The club's £72 million striker came off for the French forward with 64 minutes on the clock and that brought boos for Ten Hag as the Old Trafford crowd vented their frustration at the Dutchman.
Joao Pedro made it 3-0 to Roberto De Zerbi's side after 71 minutes and although Hannibal Mejbri pulled one back for United with his first ever goal for the club after that, it was a disappointing afternoon for the home side.
And there were more boos for Ten Hag and United at the final whistle as the Old Trafford fell to their third defeat in five Premier League games this season – and their first at home in 2023/24.
United are now 13th in the Premier League with just six points, while Brighton are in fourth with 12 from their five fixtures.
For the Seagulls, it was a fourth straight win in the Premier League against United and a second successive victory away to the Red Devils. "We just love playing here," their official Twitter account wrote after the game.
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