Manchester United stunned at the John Smith's Stadium as Aaron Mooy and Laurent Depoitre gave Huddersfield their first win over their illustrious opponents since 1952.
After the match, Herrera claimed the United players didn't match Huddersfield's passion and aggression.
And Mourinho was furious with his midfielder's assertion.
Mourinho said: "I heard Ander Herrera in the flash interviews said the attitude and desire was poor, oh my God.
When a player thinks that then I think all players should go to the press conference and explain why because I can't explain
Jose Mourinho
"When a player thinks that then I think all players should go to the press conference and explain why because I can't explain.
"It concerns me of course. If it happened today then why can't it happen tomorrow?"
Herrera admitted United were second best to the Terriers.
Reuters
Ander Herrera had a poor match for Manchester United
He said: "In the first 30 or 35 minutes, we didn’t play good. They were more passionate than us, more aggressive. We cannot accept that.
"Congratulations to them, they deserved it, but we have to analyse where we lost today. We lost almost every ball. That cannot happen in the Premier League.
"Everyone has to analyse for himself what happened in the first half. When you play against a team that normally you are better than, you have to match their aggression and passion. We didn’t do that. It cannot happen again.
"In the second half we were OK. We tried to move the ball. It was OK, but not enough for a point."
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