Fernandes has missed two of the three penalties awarded to United in the Premier League this season - one in a 1-1 draw at Fulham and another during a 3-1 defeat to Brentford - but Amorim expressed full confidence in his captain ahead of Sunday's trip to Anfield.
The Portuguese midfielder did successfully convert a decisive penalty in the 3-2 win over Burnley in August, and Amorim pointed to Fernandes' long-term record as justification for maintaining his role as the club's main taker.
"Yes, he's the main taker," Amorim said. "I think he has 70 penalties and he misses nine - two with me. I'm really annoyed with that," he added, with a chuckle, "but he's really confident. He's training the penalties, trying to understand that people are watching the way he scores. He will be ready."
Before this season, Fernandes had not missed a Premier League penalty since December 2023 against Chelsea. Across his career, he has scored 62 of 70 penalties, a conversion rate of nearly 89 percent.
At United, he has scored 39 of 45, slightly lower at 86.6 percent, but still a strong return. Amorim acknowledged that the recent misses came at important moments, directly impacting results, but insisted there is no need to make a change yet.