Liverpool travel to Old Trafford a week after Ole Gunnar Solskjaer's men held the defending champions to a draw in the Premier League at Anfield. However, since then, Jurgen Klopp's side suffered a shock 1-0 home defeat to Burnley during the midweek, but Fernandes knows the Reds can bounce back at any point.
"I think teams have moments. I don't think Liverpool are playing poorly. I think they don't win and this is the point," Fernandes told the official Manchester United website.
“When teams don’t win, everyone talks about that. When players don’t score, everyone talks about that. I feel that on me because I know the standard is high, because I arrived and I scored a lot of goals and make a lot of assists, and everyone is wanting goals and assists from me. It is the same – everyone expects goals from Salah, from Firmino and from Mane.
“They are not scoring in the last games and it starts feeling like ‘oh, they are not playing well’. They create, they play, but the other teams are playing better and, as I said before, they have more qualities to play.
"Every team goes there to play maybe without the pressure of the fans. Teams play a little bit more comfortably and, as I say, I think it is a moment. We don’t have to look at that moment because big teams and big players can show in every moment.”
Meanwhile, Fernandes is hoping to beat Liverpool for the first time since joining United, and will be eager to make amends for missing a fine chance to win last weekend’s game at Anfield.
“In the past already I have seen Manchester playing for a long time and I know what that game means for the fans,” he added. “Everyone knows and of course, for us, it means a lot because it is a cup [tie] and it is a chance to put one of the strongest teams who are in the cup with us out, so we have to take that.
“Of course, we have so many teams in the cup in this moment that maybe you can have an easier game than this. But if you want to win the cup then you have to beat the biggest teams, so we have a chance now to beat one of the best that is left in the FA Cup.”