Amorim’s side earned a much-needed Premier League win over newly promoted Sunderland at Old Trafford on Saturday (October 4).
Mason Mount scored the opener before striker Benjamin Sesko secured all three points with tap in on the 31st minute mark.
Speaking to BBC Sport after the game, Amorim praised his side’s ability to earn the win with a relatively comfortable performance.
He said: "That is the kind of game where when we're not playing well we're defending well. We had our moments, we were focussed and competitive.
“Not the perfect performance. Senne (Lammens) did really well. We were a competitive and adult team today. We need to win these games with a clean sheet. Good for us.
"We need to understand that we need everyone to be ready to play. It's a long season, we have a lot of problems, anything can happen.
“The important thing is that the teammates helped Lammens a lot to have a very good performance."