Erik ten Hag's side suffered their 15th defeat of the season in all competitions as Alex Iwobi's 97th-minute strike clinched a 2-1 win for Fulham at Old Trafford, ending United's five-game winning run and severely damaging their top-four hopes.

Their performance, described as "absolutely shocking" by Merson, laid bare the size of the task facing new part-owner Ratcliffe as he attempts to restore the club's former glories.

Merson believes their recent winning run merely masked their continued issues under Ten Hag and insists any manager who guides the club to the title in the next five years deserves a knighthood.

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"Man Utd were shocking. I'm not exaggerating. Absolutely shocking," said Merson on Soccer Saturday.

"How they think they can get in the top four… What's the point in getting in the top four anyway? They're not going to win the Champions League, so what's the point in being in it?

"I thought Fulham did very well. They grew into the game and it was comfortable. They absolutely dominated the first half. They thoroughly deserved to win. It wasn't a smash and grab. Far from it.

"I can't explain how bad Man Utd were. It was so, so bad.

"No one played well. (Marcus) Rashford, no. (Alejandro) Garnacho, no. (Bruno) Fernandes, no. Even (Kobbie) Mainoo got subbed. Noone today. Maybe (Harry) Maguire for effort. He got the goal and he should have scored another one.

"But, honestly, really, really poor. [Sir Jim Ratcliffe] will be watching that today thinking 'Wow, I put a lot of money on this.' You put all that money in and watch that today, they are a [million] miles away.

"The players as well. They are a [billion] quid away. I don't know how they're going to catch up. He said he wants to overtake Man City. Woah, pull it in. Try and take over a few of the others first."

'Wins covered over the cracks'

Asked about their recent winning run, Merson added: "They have all been 'Pollyfilla' results in the last five or six weeks. They have just been covering over the cracks.

"They scored with the last kick of the game against Wolves. It was snatch and grab at Aston Villa. They weren't better than Villa that day. They beat West Ham 3-0 but that was never a 3-0 football match.

"They were covering over the cracks and they got found out again today.

"Only Sheffield United have got fewer points away from home this season than Fulham, so it's not like they are serial away-day winners who know how to play away from home.

"Man Utd are a million, million miles away from Man City. It's at a stage now where you look at Man Utd and it's like it was with England about 10 years ago, when you used to say, 'I'm not sure they will win a competition in my lifetime.'

"That's the way it is with Man Utd at the moment. I don't see them winning the league any time soon. They need to go and get Dan Ashworth. I'd rather pay £30m for him than a £30m player. They need to start from the bottom.

"But this is going to be very slow. It's not going to be overnight. If Man Utd went and won the league in the next five years, whoever is the manager should get knighted. Seriously.

"Get that team to win the league over 38 matches? Absolutely no chance."

Sherwood: It might be longer than five years

Tim Sherwood was similarly downbeat on United's future prospects, pointing the finger at Ten Hag for his role in the club's questionable recruitment during his tenure so far.

"I think it might be longer than that [five years]," he said.

"We talk about them needing players but a lot of them are the manager's players. They are players he has brought to the football club, so something is wrong.

"Maybe it's identification of players, maybe the competitive nature of the Premier League.

"This is the most competitive league in the world. He needs players who can play consistently and compete every week and at the moment they haven't got that.

"If I was Sir Jim Ratcliffe, would I be giving him another £200m-£500m? Not on the evidence of what I've seen him do.

"If they finish outside of Europe, I'd be shocked if Ten Hag was still there in the summer."

'Forson let down by senior players'

Ten Hag handed a first Premier League start to 19-year-old Omari Forson in the absence of the injured Rasmus Hojlund against Fulham but the academy graduate struggled to make an impact before his withdrawal early in the second half.

"I felt for Forson," said Merson. "He was getting frustrated with himself. He lost the ball a couple of times.

"But when you come into the team for your full debut, you've got to rely on the older players. They've got to play well and he didn't get that today.

"None of the players around him played well and I don't think it helped him.

"I really felt sorry for him. I felt the older players let him down, not giving him the ball in proper places, looking after themselves.

"But it was an experience. He's made his full debut for Man Utd at a young age and he should be proud of himself."

Ten Hag: We showed character but let them escape

Ten Hag insisted he was happy with the character shown by his players and bemoaned the errors that led to Iwobi's winning goal.

"We showed big character by fighting back and then we had opportunities to win the game," he told Sky Sports.

"We let them escape because one player takes the wrong position. Don't let them escape from a throw-in in the corner.

"Fulham are a good team but we could have pressed better. After we found out how to manage that, I think we got better in the game. We had very good chances.

"They had chances as well but, during the first half, I had the idea we got better and better.

"We had a slow start in the second half and we lost Casemiro, which cost us the goal.

"We had strong belief. We went for the win. That is the character from this team and that is great to see."