Speaking to BBC Sport, Chris Sutton said: "When it comes to predictions, I honestly don't know what to expect from Manchester United. Even when they were on a winning run, they were not controlling games.
"I backed Man United to win at the weekend too, but the worst thing about their home defeat was that Fulham fully deserved the three points. Nottingham Forest beat United at the City Ground at the end of December.
"And they have still got a goal or two in them although their league form since then has not been great. In contrast, Man United offered little against Fulham without the injured Rasmus Hojlund to lead their line.
"I put Marcus Rashford in my Fantasy team, and he barely had a kick. Man United are good on the counter, but they need to finish their chances, and Hojlund is such a big miss. This tie feels like it going to be very close.
"It could go the distance, but I think Man United will find a way to edge it. I don't know why, because there is more pointing towards it going the other way — I guess this is probably why I get so many Man United scores wrong.
Sutton's prediction: Nottingham Forest 0–0 Man United, the Red Devils to win after extra-time and penalties
Man United will be looking to bounce back with a positive result against Forest on Wednesday after a disappointing defeat against Fulham in the Premier League.
FA Cup remains the Red Devils' only shot at a trophy this season as pressure continues to mount Erik ten Hag following an minority stake purchase by Sir Jim Ratcliffe.
