Amorim worked with the United midfielder at Sporting CP before he was sold to PSG.
Ahead of Saturday's clash with Nottingham Forest, Amorim discussed the fitness of Ugarte and captain Bruno Fernandes.
He said, "You have an idea but then you have the problem of players returning without training and then you have to manage the load. So you also have the same problem but then you have to imagine and understand what kind of player you have. Bruno Fernandes, you feel it, against Arsenal, in the end, he was a little bit tired but you know he is going to recover very well.
"Manuel Ugarte, I've known for so long, I know that he needs sometimes a little bit more time. So we are in that process, to know the players and try to manage that, but we're getting closer to an idea, yes."
On finding consistency, Amorim also said: "Yeah, it's sad because it's very competitive in this league. It changes all the time with just one result and, sometimes, when you're doing progress, you can do so much and then you see this kind of result. We have to pass this phase.
"So I can feel the same way because, before the Arsenal game, you guys were asking about the top four and now we return to this position. Nowadays, it's like that and we have to manage expectations and, at the same time, when we have a bad result, we have to be calm and continue to do the job that we are doing."
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