James Lawton: Making himself indispensable top of Van Gaal's achievements
Klopp's availability of no concern to United supremo as Young and Rooney reflect his revival
For compelling reasons many think of him as the sorcerer of football but then tomorrow evening the worshipping fans of Jose Mourinho might just be forced into seeing him in a rather different light. Not as the sorcerer perhaps but, just maybe, his apprentice.
That is certainly the threat Louis van Gaal, his old boss at Barcelona, carries when he arrived at Stamford Bridge with a Manchester United apparently fully healed in both heart and sinew.
If you study the managerial records of the 63-year-old Dutchman and Mourinho (52), you are reminded of stories of largely unbroken success. The latter has an edge in titles, and one more Champions League prize.
Yet this - in the context of a duel which might just bring a competitive glint to the title race which most conceded to Chelsea some weeks ago - is surely balanced by the fact that Van Gaal's restoration work at Old Trafford is beginning to touch on the miraculous.
Already he has cast shadows over the long-term employment prospects of rivals like Brendan Rodgers at Liverpool, Mauricio Pochettino at Tottenham and, most bitingly, Manuel Pellegrini at Manchester City.
Impressive tactical triumphs by United have left all three of them vulnerable in this week's news that Jurgen Klopp, the miracle worker of Borussia Dortmund until he had his team sold from beneath him, has decided to seek a new challenge.
Inevitably the German will have Premier League suitors and if Van Gaal pulls off still another coup tomorrow Chelsea, already buffeted by banishment from Europe and a stuttering stride in the title race, might just be one of them.
Chelsea owner Roman Abramovich wore a glassy expression when Paris St-Germain celebrated their triumph at Stamford Bridge and another one is guaranteed should United maintain their current run.
Indeed, and despite Arsene Wenger's recent nibbling at old glory, only Van Gaal of the Premier League's elite managers currently appears to be bombproof.
In the last few weeks he has not only turned back a tide of criticism flowing around what seemed to be his laboured attempt to refashion and reanimate the slumbering giant, he has created the prospect of an achievement which seemed beyond the powers of even the hard-headed veteran who guided the Netherlands so impressively into third place in last summer's World Cup.
He has come close to guaranteeing an instant return to the Champions League, and a victory tomorrow might just provoke a previously unimagined late run at the title.
It is a body of increasingly stunning work.
Wherever he casts his Sphinx-like gaze Van Gaal can point to a team filled with individuals fighting to make career statements.
Nowhere is this more obvious than in the demeanour of 29-year-old captain Wayne Rooney. Re-installed at the head of attack, Rooney's commitment has never been so apparent.
When United appeared to be unravelling before Alex Ferguson made his last-stand title success, Ryan Giggs made a famous speech in which he said that the dedication of the Old Trafford dressing-room had never been more questionable.
At the time Rooney had slipped some way from the favour of Ferguson, but now he appears to be at the heart of the revival.
It is a pattern which has recently developed quite seamlessly through the team, with only Angel di Maria currently outside looking into a circle of ferocious effort.
Tomorrow one of the re-claimed, former Stamford Bridge favourite Juan Mata, will no doubt attract the most acute attention.
Twice voted Chelsea's player of the year, the Spaniard was swiftly discarded by Mourinho. Yes, said the Special One, he could score goals, he could catch the eye, but for his purposes he was simply too peripheral. Now Mata has nudged his goals total to eight and is increasingly a key to United's fertile raiding.
Inevitably, Mata's performance will be compared to that of his compatriot Cesc Fabregas. If it happens that their mano-a-mano battle proves significant, and Mata is the winner, Mourinho is surely guaranteed another baleful post-game expression from his oligarch master.
For Mourinho, the big hope is that Eden Hazard continues the remarkable form that makes him most people's favourite for the player of the year awards.
Also he must pray, maybe to a favourite object of devotion, Our Lady of Fatima, that his team can re-create some of their old poise and conviction. Certainly he knows that he faces a team running at optimum levels of both confidence and optimism.
The more you analyse Van Gaal's campaign the more remarkable it becomes.
And the more bizarre Rodgers' pre-season claim that the Premier League represented a new and potentially treacherous challenge to the composure of a man who had so confidently negotiated the Dutch, Spanish and German leagues.
With his first Premier League season still awaiting final definition, Van Gaal's effect has been dramatically reflected in the performances of his key players.
Ashley Young (below), who seemed to be drifting away from serious consideration as part of United's future, was outstanding in the demolition of City last weekend.
From the moment of his early equaliser, he was a force which wiped out the advantage of Sergio Aguero's brilliant opener.
Also hugely influential was the scoring bite of Mata and the statesmanlike touch of Michael Carrick in midfield. At 29, and in his ninth year at Old Trafford, Carrick looks like a man he who has re-invented the best of himself.
So too does Marouane Fellaini. Booed by the fans, the despair of his old Everton mentor David Moyes, Fellaini seemed to be just another displaced person.
Now he is integral to the United renaissance and, according to Old Trafford insiders, pronounced 'undroppable' by the manager.
It is, plainly, a heady collective state of mind United take to Stamford Bridge, even if the bookmakers keep their faith in the enduring quality of Mourinho's methods by making Chelsea odds on at 10/11 and offering Van Gaal's men at 5/2.
This, though, still represents a leap in confidence in the future of United by the least romantic inhabitants of the football jungle.
Whatever happens tomorrow, they seem to be saying, Van Gaal's tenure is likely to remain rock-like for some time.
That, for the most moment at least, has to be right at the top of some quite remarkable achievement.