ALEX Ferguson, Wayne Rooney and even a Manc like Ryan Giggs have spent the week dismissing it, but it's happened before. In 1968, much like today, Manchester United were a few months one side of a European Cup win, had some of the finest attacking players around and were swashbuckling league champions. City meanwhile, much like today, were on the back of a mediocre decade in which they'd spent time outside the top flight but were emboldened by enigmatic leadership at the top and some landmark signings which signposted a team on the up. Against odds, their relative novices beat United's names 3-1 to set up a league title won on goal average and also the only period since the second world war in which they were Manchester's more successful club. Many observers – the majority, admittedly, in the blue corner – have since called it "the most important Manchester derby ever".

Much like today? We'll have to wait and see.

Robinho may be a more glamorous signing than Mike Summerbee or Colin Bell, but Sheikh Mansour and Khaldoon al Mubarak are not even a fraction as far into their plan as Joe Mercer and Malcolm Allison were 40 years ago. The difference is the effects of the modern-day figureheads could be far more emphatic and far more extensive.

The most important derby ever then? Not yet, but certainly the richest. Not just in the city or in Britain, but the world. It's perhaps fitting since the first time the two teams met with their current names – as opposed to Newton Heath and West Gorton – the gate receipts exceeded £1,000, an obscenely high figure for 1906. Just like the numbers for today's game. Both clubs after all have legitimate claim to be the richest in the world, if in different ways. United thanks to Forbes valuation of €1,500m, City thanks to the €1 trillion Nahyan family fortune they can dip into.

Of course so far we've only seen a glimpse of City's market power. But by swishing away Robinho it was sufficient to give one of the biggest of the Big Four, Chelsea, a bloody nose while the one-instalment payment of that £32.5m fee suggests that in January they could make Roman Abramovich's spending in 2003 look parsimonious and lacking in ambition. Quite simply, the Abu Dhabi group are on a different level, untouched by global recession the way Abramovich is.

However unrealistically, Chelsea names like John Terry and Ashley Cole, as well as global superstars like Gigi Buffon and Kaka, have been mentioned and if even a few arrive to impact in the way Robinho has, City could yet make a charge up that bodice-tight table.

Indeed, Robinho's growth from spoilt infant to spectacular inspiration over the past three months is a story nicely fitting with City's own transformation. This, after all, is a player who on leaving Spain was described as "the lad who could have been the next Pele but ended up the next Denilson". Since departing Santos in 2005, he hasn't been known for spectacular strikes or stepovers as before, but for strikes of protest and stepping over responsibility. The Spanish and Brazilian press lambasted his behaviour, his infrequent flashes of brilliance and his inability to perform in big games – during one Brazil-Argentina match Dunga was even caught saying on the bench "Robinho looks afraid".

There's been no such fear since he arrived at Eastlands though as instead he's even captained the side and scored eight goals in 11 league games – two of them against Chelsea and Arsenal. Next up United and the chance to upstage Cristiano Ronaldo.

He already intimated it during the week when he brought up Brazil's 6-2 thrashing of Portugal, but this could be something of a personal duel for Robinho. Ronaldo was after all the reason for his most recent blip and his arrival at City. Because, far from a rebirth, Robinho's form could merely be said to be a continuation of that which he enjoyed at the start of the year, a 10-game run that effectively saw him win Real La Liga. Just after the "40 condom" controversy on a trip with Brazil, it coincided with the first time a manager in Spain actually mollycoddled him, as Bernd Schuster did. Robinho however got injured and on his return found the club very publicly chasing Ronaldo with his sale expected to fund it. One of the lowest paid at Real – even behind Royston Drenthe – his requests for a new contract were denied until after the Ronaldo deal was off. The sort of treatment, in other words, that made his seemingly petulant behaviour understandable.

During that time, one of the few to defend him was former Real director Arrigo Sacchi. And rather than a happy-go-lucky trickster, Sacchi maintained Robinho suffered from low self-esteem and constantly needed encouragement. At City he's finally found it, with close friend Elano introducing him to the city's Little Brazilian hub. Tellingly, he's signing his name with a smiley face again.

He would of course also have found a familial compatriot at Chelsea, but Felipe Scolari has arguably come out worst from his side's failure to strike a deal with Real. On the intermittent occasions when Chelsea have been unable to physically steamroll a team – Newcastle and Bordeaux most recently – Scolari has put it down to lacking the sort of extra dimension Robinho provides. Only three weeks ago he said: "When I started here, I said I wanted one player who is different – someone who will try something different when we play against teams who close us down… Robinho dribbles and makes a difference." When Chelsea failed to secure his signature on deadline day Scolari was pu blicly gracious but privately said to be apoplectic.

How many times City can cause Chelsea and the rest of the Big Four such anger again is another issue though. The Robinho signing came out of a unique situation – the player's desperation and Abramovich's caution in the new financial climate – but City as yet don't have half the cachet of the rest. The Stone Roses' Ian Brown may have said Manchester has "everything except a beach" but many of the world's top stars evidently don't think so. One of the reasons Ronaldo wanted out of United was lifestyle and it was only Ferguson and the club's prestige that persuaded him to stay. The successes of the '70s notwithstanding, City don't have that pull. But although the likes of Dimitar Berbatov and, lately, Buffon scoffed at their interest, Gianluca Vialli rebuked his compatriot: "It could be a very intelligent move and if I was Buffon I would consider the deal."

By law of averages City are bound to hit a few of their many "top targets" in January and that ability to spend money – combined with Rafael Benitez's inability and Arsene Wenger's reluctance to – could see them rise sooner than Ferguson thinks.

Until January at least though, the fact remains City are a club in transition. A win today will not only help Mark Hughes but also City's pulling power. They may be fortunate in that they're playing a United side that has yet to win any of their big games this season – Liverpool, Chelsea, Arsenal, Everton, Aston Villa – even if all were away from home. On the other hand, Ferguson might be determined to prove his point about City's status.

It's far from the most important derby ever, but it could still be a telling one.

mdelaney@tribune.ie