Since his troubled start, Ferguson has been almost immune to the sort of slumps that have accounted for umpteen others, as Fabio Capello admits he is best ever.
Ferguson is making history as longest serving manager
After almost a quarter of a century, games can fade from the memory as the weeks and months can merge into one.
Yet, even by his own exalted standards, this is still a notable seven days in Sir Alex Ferguson's long reign at Manchester United. One distinguished manager has been defeated. Now another is being displaced.
On Monday, Arsene Wenger was outwitted as Arsenal went down 1-0 at Old Trafford. Now Sir Matt Busby is overtaken as Ferguson becomes the longest-serving manager in United's history.
The postponement of today's game at Chelsea prevents Carlo Ancelotti from becoming the third scalp of the week. Respite for one Italian manager came soon after the compliments from another.
"In the history of football, the best manager is Sir Alex," said Fabio Capello, the England coach.
Beating Busby is merely a by-product of the years, but time itself is a feat in a profession that has spat out dozens of imposters. Since his troubled start, Ferguson has been almost immune to the sort of slumps that have accounted for umpteen others, one of which now endangers Ancelotti.
The last great dictator has manoeuvred himself into a position of complete control. The Glazers, the United owners, acceded to it, because no one protects their investment better.
It is to his credit that, whenever events threaten to spiral out of hand, he invariably regains the reins of power.
Hence the rebellious Wayne Rooney is restored to his role as the spearhead of the attack, rather than preparing for a new club in the New Year.
The ever-present at the helm has a neat line in resurrections; Anderson's new four-and-a-half year contract is the sign of a player who has revived a United career some considered barely worth saving.
He wins arguments by winning matches. Results are the ultimate rejoinder. But while Ferguson appears unstinting and unbending, Capello's tribute was instructive. The dinosaur has evolved.
"For such a long time he managed the team and he has changed a lot of things," Capello added. "He changed the team, he changed the players, he has been really, really good for the club."
Indeed this season United they have been, like Ferguson, a constant and a chameleon, never beaten but never quite the same: careless in losing leads against Fulham, Everton and West Bromwich Albion, escapologists against Aston Villa and Wolverhampton Wanderers, brilliant against Blackburn Rovers, resolute against Manchester City and Arsenal.
Strangely fallible at the back earlier in the campaign, they have been increasingly reliable since Rio Ferdinand resumed his central defensive partnership with Nemanja Vidic.
Ji-sung Park has veered between mediocrity and match-winner, Dimitar Berbatov has been fantastic and frustrating, Paul Scholes superb and then sidelined.
As the years go by, the chances of his players outlasting him recede. Ferguson turns 69 on New Year's Eve but Scholes, like Gary Neville and Ryan Giggs, is likely to have retired before he does.
There was a hint of hyperbole in Capello's words - "I wish him another 20 years of management at the top level" - but you never know.
A part of history, Ferguson continues to make it.