The Red Devils picked up a hard-fought three points with a 2-1 win over Sheffield United, but it was a tricky watch throughout.
After a 1-1 first half that saw goals from Scott McTominay and Ollie McBurnie, things became increasingly cagey in the second period at Bramall Lane.
In an effort to free things up, Ten Hag made a triple substitution, which didn't get a good reception.
Calling the changes, talkSPORT's Ian Danter said: "Anthony Martial is coming on for Rasmus Hojlund and you can hear a few boos, I don't know if that's over that particular withdrawal.
"Scott McTominay makes way for Christian Eriksen, and you can hear what they think of that! The idea of their goalscorer being taken off.
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"An interesting response from the Manchester United fans."
Those changes came in the 63rd minute of the match, but soon after the away end was in raptures.
Diogo Dalot scored perhaps the best goal of his career, bending in a sublime strike from distance to put United 2-1 up, and claim the three points with a goal worthy of any match.
Coming on the day club legend Sir Bobby Charlton passed away, Danter commented: "An effort that Sir Bobby would have been proud of himself.
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"My word! He wrapped his foot around that so beautifully to find the top corner, beating the grasping hand of Wes Foderingham."