Amorim’s side have a crucial clash against high-flying Sunderland on Saturday (October 4) after their humiliating 3-1 defeat to Brentford in the previous round of fixtures.
The Portuguese manager is under growing pressure at Old Trafford having amassed just 34 points in 33 league games as he continues to persist with his failing 3-4-3 system.
He has threatened to quit several times since replacing Erik ten Hag last November, but he now insists that won’t happen.
Speaking to the press, Amorim said: "That is a decision of the board. I cannot do that. Sometimes I have that feeling and losing is hard. It's so frustrating when you create the momentum, go to the next game, and something happens.
"That feeling sometimes hurts me a lot. Also the players and especially the staff here.
"But that is not my decision. And I think it would be really hard to leave if I don't do everything to follow my career here."