The 39-year-old opened up in an interview with United legend Gary Neville on Sky Sports about how hard it was to leave the Portuguese club halfway through the season.
“It was really hard but I had to do it,” Amorin told Neville. “I already had conversations with clubs so was quite normal but what I felt at the time, I felt that this is my place.
“I think it was the right club in the right moment for me, Amorin continued. “I felt that this is my place. I think it was the right club in the right moment for me.
Sporting sit top of Liga Portugal and will challenge for the title this season which is something United are very far from. Amorim was honest about how he feels about leaving his former side but he still feels it was the right decision.
“It was very tough to leave Sporting. Because in the middle of the season, you can say everything, it's Manchester United. It's everything, it's the moment, it's the club that I want.
“But you are leaving your guys in middle of the season. It was really hard but I had to do it and I was so happy, of course.
“You can see it in every interaction that I have but I also felt in the first moment it was a little bit overwhelming. But after five minutes you start thinking about the club, the team, the players, how to play.... so it was quite fun.”
Amorim takes charge of his first game this weekend as United clash with Ipswich Town away from home.
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