Manchester United s head coach Erik ten Hag, right, reacts during the English Premier League soccer match between Manchester United and Crystal Palace, at the Old Trafford stadium in Manchester, England, Saturday, Feb. 4, 2023. (Photo: AP)
Bruno Fernandes' early penalty and a Marcus Rashford strike put United on course for a 13th successive home win in all competitions.
But Ten Hag's team had to survive a nervous finale at Old Trafford after Brazil midfielder Casemiro was dismissed before Palace's Jeffrey Schlupp scored to reduce the deficit.
Just prior to his goal, Schlupp had shoved United winger Antony off the pitch, sparking a fight involving both sets of players which ended with Casemiro receiving a straight red card for violent conduct.
Referee Andre Marriner was advised to check the pitchside monitor by the VAR to review images of Casemiro grabbing Palace's Will Hughes by the throat.
"It was a really high level first 70 minutes until the incident takes place and then you see this team stands for each other," Ten Hag said.
"It's such a good spirit for the team and they don't accept when a player from us can be badly injured. That is the way Antony got treated.
"This team sticks together, but of course you have to control your emotions, but it's really difficult in such a moment.
"Then I see two teams fighting each other, I see two teams where players, several players, are crossing the line and then one player is picked out and sent off. For me, that's not right."
United's victory consolidated their grip on third place in the Premier League.
Gloss was taken off the result by Casemiro's red card and Ten Hag said Schlupp took a "big risk" by shoving Antony off the pitch, saying he could have been "badly injured".
The Dutchman also claimed Palace's Jordan Ayew should have "definitely" been sent off for his actions in the fight that followed, with the recent lack of VAR consistency infuriating him.
"You bring it up, but that was one of the players who did even worse, I would say, than Casemiro," Ten Hag said of Ayew.
"With Casemiro, you freeze the moment and he's crossing the line there, but I do definitely.
"You have to be consistent as a VAR. Last week we missed Christian Eriksen (who is out for three months) by a bad foul. No interference from VAR.
"In Crystal Palace (last month), (Jean-Phillipe) Mateta is elbowing (Lisandro) Martinez, he is running for two weeks with a mark on his eyebrow and (VAR's) not interfering. I see this is not right."
Crystal Palace boss Patrick Vieira was also furious with the officiating.
Vieira stormed straight over to Marriner at full-time, but, asked what he said to the officials, he replied: "I don't want to talk about it."
(For more sports news and updates, follow Ahram Online Sports on Twitter at @AO_Sports and on Facebook at AhramOnlineSports.)