Ahead of Sunday's derby, Amorim was asked if City had made an approach when he was Sporting CP coach. Amorim had been mentioned as a successor for Pep Guardiola earlier this season before taking the United job.
"Never. Never had and this was my only option," said Amorim.
"When Manchester United talked to me, I had no doubts because I had already something in my mind it could be a possibility.
"With Manchester City or Hugo Viana? Nothing about that."
On City's current crisis, Amorim also said: "I never think about these things. We will face a great opponent and I'm more focused on our problems, so we have a lot of issues here.
"I'm more focused on what we should do on Sunday to win the game, so I'm really focused on my team.
"The great teams can respond in any moment, and I think they are in a better place than us in the type of understanding the game, the way they play, the confidence they have. Even in these kind of moments.
"We have a lot to focus on in our team. Of course we have a strategy to try to win the game with the strategy like it should be, but we are focused just on our team."
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