Ralf Rangnick did not mince his words 12 months ago when describing the extensive work that would be needed to be done when Erik ten Hag arrived at Old Trafford.
"You don’t even need glasses to see and analyse where the problems are," Rangnick said. "Now it’s about how do we solve them? It’s not enough to do some minor amendments – cosmetic things.
"In medicine, you would say that this is an operation of the open heart. If this happens and everyone has realised that this has to happen and if people want to work together then it makes sense and I believe it doesn’t take two or three years to change those things. This can happen within one year."
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For all Rangnick was castigated by some intellectuals within the football media, his assessment that with the right work, it can only take one year was correct.
It is easy to forget how much of a mess United were. They lost all of their last six away games in the Premier League, one of which included a 4-0 demolition at Anfield. The dressing room appeared fractured, a team of individuals on the pitch, and supporters were naturally miserable for the whole season. Sound familiar, Chelsea fans?
12 months on, United look above all else, like a competent football team again. A collective that is not flawless but is more akin to a group reflecting the value that has been invested in it. A comfortable victory over this current Chelsea side was not significant given the Blues' turgid displays this season, but it confidently assured Champions League qualification for next season.
With 72 points for Ten Hag, they have already bettered last term's total by 14, with the chance for one more win on Sunday against Fulham. Add to that the triumph of a Carabao Cup, a memorable win over Barcelona and the resurgence of Marcus Rashford - plus an FA Cup final against rivals Man City coming up - and the positives far outweigh the negatives.
This is the blueprint Mauricio Pochettino will be aiming to replicate at Chelsea next season. Ten Hag has not had things all his own way this year and there have been some very public losses. The 7-0 humiliation at Anfield, worse in scoreline than last term, stands out as a bleak day. As was the collapse over two legs to Europa League specialists Sevilla last month. It is easy to forget that Ten Hag began his reign with consecutive defeats to Brighton and Brentford; back then, there were already questions over his ability to coach his system.
There was also the superstar problem of Cristiano Ronaldo which could have undermined his power with the forward's public outbursts when not being brought on against Spurs. But in both cases, he has come out stronger. Adapting his style to the tools in front of him in order to gain results and with Ronaldo, did not bow to the pressure of stardom opting instead to lean on players who tactically fit his approach.
Whilst Chelsea do not have a Ronaldo, they will have older heads that will need to manage smartly after a chaotic period. Even if Chelsea's intended summer car boot sale manages to trim the squad to a more reasonable size, there are still players with question marks over their future.
Pochettino has proven in his career he is a strong enough character to make bold decisions and dismiss with those who do not serve the overall plan.
No quote summarised the Argentine's sentiment better than when detailing his approach to managing new players. "When a player signs a contract, they need to understand that they do not sign a contract to play games. You sign a contract to train. Then you wait for the manager to pick the team."
Frank Lampard has done little to aid his coaching credentials in a bruising caretaker spell since Easter, but he stressed how good of a job this can be with the talent available to his successor after the loss at United. "I think it is a fantastic job because it is the Chelsea job. When I took it the first time I came in, I knew I got it because a lot of top managers didn’t want it [because of the transfer ban], I know that for a fact.
"I enjoyed the process and I enjoyed coming in and I wish the new manager well. I don’t know [if it will be hard], that’s his problem."
In the opposite of Lampard's 2019 arrival, Pochettino does not have a crutch of too few players, his biggest headache currently is boasting too many. However, this position does not need to be a poisoned chalice, something that you could have accused the Man United position as being last year.
Football changes quickly. Pochettino, Chelsea and a bruised new ownership will be hoping Ten Hag is a sign Chelsea's "open heart surgery" can be as smooth.
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