Slaven Bilic have faith in Phil Jones' tackle on Sofiane Feghouli was more dangerous than the challenge which saw the West Ham midfielder sent off.
Feghouli saw red after 15 minutes at the London Stadium when he conflicted in a sliding challenge with Jones.
And while Sky Sports pundits slammed the sending off, Manchester United went on to win 2-0 and earn their sixth league win in a row.
Sofiane Feghouli styles a challenge on Phil Jones resulting in his sending off
Sofiane Feghouli makes a challenge on Phil Jones resulting in his sending off
West Ham boss Bilic believes Jones "made a meal" of the test, with his reaction helping Mike Dean make his decision.
"It was never a red card to be fair. It was a challenge from both of them," Bilic said Sky Sports.
"It was the other method round in terms of who did the more dangerous tackle. It was Jones. Okay he's carrying the ball but he went in with the scissors.
"Phil made a meal of it, but you can't responsibility him doing that. Maybe he made a meal of it because he went with the dangerous one to save himself.
West Ham 0-2 Man Utd
To watch Premier League action on your mobile now download the Football Score Centre on iPhone or Android
"You have to realize who is doing our test. It's Feghouli, who very rarely makes a foul in the game. His foot wasn't high in the air and it wasn't thoughtful.
"For me, that was the crucial decision in the game. That early - it killed us. It put the game in a totally different perspective.
"That decision and the other one [offside goal] were totally unfair to us and totally incorrect."
Jose Mourinho says West Ham made it tough and was relieved his Manchester United side left the London Stadium with a victory