The former Wolves striker has quickly impressed his new manager.
Amorim told manutd.com: "More than the results, it’s the way that we perform that helps to give confidence," began the boss when asked about morale in camp.
"Then I think the group is really good, I said last year we can do so much more with the same players.
"All the work that we did before buying Matheus and Bryan (Mbeumo), all that work behind the scenes to know the players, to talk with people that played with the guys, was really important because they are everything that we were expecting.
"(They are) great guys and great players, so we are in a good place."
It's a positive aura that seems to be well echoed around United's pre-season endeavours, especially given our results on the pitch, too."
On Cunha, Amorim also said: "He’s a loud guy that’s really important in this moment. When he’s upset, you can feel it in the environment and that’s good.
"When you play some games and he loses, he’s a different guy, and that’s good. He has some characteristics that we miss last season, so I’m really happy with him and the other guys."