The Portuguese was asked for his thoughts after United claimed an unlikely point against the league leaders.
Having gone into this game in 14th place in the table, United were very much outsiders.
Amorim stated: "I want to see my team to play so much better, but I think the most important thing to address today is the mentality. And that is the key for everything.
“So today we were a different team, not because of the system, not because of the technical aspect of the game, the tactical aspect of the game, we faced the competition in the way that we’re supposed to face every day - training and match. It doesn’t matter the place, the opponent, we need to face every day like that."
On challenging his players, he added: "I am trying that every day, I am trying to push this team every day. Sometimes it is maybe not the best way, because I’m always challenging these players in everything I do, because I feel that we are - not just the players - but everybody in Manchester United is too comfortable. So I think we need sometimes a shock. And you can see it today, we were a different team. It’s not about the system, it’s the way we face the competition."
On Bruno Fernandes stating they need to play this way more often, he finished: "Yeah, I think it’s a very good sign. It’s really clear. We lost three games in a row at home. Some of the games, we suffer two goals without doing nothing. So I’m upset today, really upset, because I’m pleased for the performance, but everybody today is going to say to that team that they did a good job, so today I’m allowed to be the only guy upset with the team. But today they were a team."