Fernandes scored twice on the night as United moved into sixth place on the Premier League table.
Maddison, as he recovers from knee surgery, acted as a pundit for the match and said on Sky Sports: "Well Bruno was at the heart of everything. Bruno's just such a top player.
"I actually think Bruno's... he actually doesn't have a massive part in (the second) goal, he still has the ball in the build-up. But the other goals as well. I think he's actually probably underrated to many, Bruno. And I know he gets a lot of plaudits anyway but I think he is kind of underrated, like, for the quality that he shows consistently.
"Just every time he's on the ball, he does like to always look for the longer pass; he looks short, and some players have the ability to see every pass without having to look short, look long; he can just see it all. And the quality he has, you see with the Mason (Mount) goal, it's on a plate for him. He does that time and time again, to be fair."