Mount could have played his way into contention to start against Spurs in midweek, with the boss admitting he brings a lot to the side.
"I'm really impressed," Amorim added. "I think he gives a balance to our team. He's really, really good and a really, really important player for our team. I'm delighted to have a guy like him again. I feel that this team is more balanced with him in it."
Ayden Heaven made his return from a lay-off as a late substitute and Toby Collyer was fit enough to be among the substitutes.
Of course, United have major doubts over Matthijs de Ligt and Leny Yoro, after their recent injuries, but neither was ruled out of Wednesday's final by the boss, ahead of the Chelsea game.
Diogo Dalot is also working hard to be fit enough to make the trip to the Basque Country but the good news from the capital is there do not appear to be any fresh issues.
Spurs, meanwhile, played something of a shadow side when losing 2-0 at Aston Villa, with none of their starters in the second leg of the semi-final against Bodo/Glimt in the XI. There was a scare involving Pape Matar Sarr, when he was substituted after 53 minutes, reportedly with a back problem.