On Planet Football, "invincible" is a big word, one that can empower a side all the way into the history books. Is it conceivable that United could be described as such come May? Perhaps this Sunday will be a good indicator.
The Reds haven't dazzled en route to the Barclays Premier League summit - Sir Alex's men have simply been consistent and haven't slipped up as much as the rest. But Tottenham away is a proper acid test of the Reds' ability and strength of character. The Londoners are unmistakably on the up.
Finishing fourth last season was a noteworthy achievement for a side which, in my lifetime at least, had gained the reputation of being a nearly nearly outfit. White Hart Lane has always witnessed plenty of quality football, but the success that it promised had regularly dissolved right in front of the fans' very eyes. When the going got tough, Spurs often went missing. Nowadays though, they are rightfully making themselves comfortable amoung England's elite.
This term, they have been sturdier at the back and infinitely more eye-catching going forward. The lopsided, naive and timid squads of Jol, Ramos and Santini have been balanced and remastered by Harry Redknapp, a man often touted as football's answer to Del Boy. A genius wheeler dealer on a shoestring, now he's mixing it with the big boys using proper dosh and managing growing expectations. When he took over, the team were propping up the top flight. Now they're looking down on most, including Roman's empire at Chelsea.
Harry's outfit has been bolstered by the bargain of the summer. Dutchman Rafael Van der Vaart has injected a skilful and clinical arrogance into a capable, yet at times fragile, side. The White Hart Van man's arrival has been supplemented by the jawdropping development of one Gareth Bale. In next to no time, he has been transformed from a potentially-handy squad player into a world-beating winger. Dutiful in one penalty box and deadly in the other. Oh how Mr Capello wishes this lefty had been born on the other side of the Severn Bridge. Pre-August, the mercurial Welshman had scored just 11 career goals in five seasons. The new machine-like version has plundered the same tally in just over four months.