When Manchester City face Chelsea in the big Saturday lunchtime kick-off, a club sold by a former prime minister of Thailand to Abu Dhabi royalty will confront another owned by a Russian oligarch who is a friend and ally to Vladimir Putin.

We take all this for granted now, but astonishment still strikes when the bonfire smoke from a combined £1.2bn spend rises from these games. Here we see a clash of plutocrats whose wealth derives, surprisingly, from the old?fashioned stuff: oil, aluminium, gas. We know the who, the when and the how but there is still some mystery about the why, especially in City's case. Has HH Sheikh Mansour bin Zayed bin Sultan Al Nahyan really spent £650m to watch one game - last month's 3-0 home win over Liverpool?

That blessed phrase "a football man" jumps out. How do you become one? Is there a City and Guilds or a university in the Philippines that will send you a certificate for £9.99, plus postage, or is there a minimum five?year apprenticeship at Tuesday night Carling Cup games? Abramovich and Sheikh Mansour took the fast-track to membership, buying love in the way another United Arab Emirates family, the Maktoums, virtually annexed Flat racing until Ireland's Coolmore mafia fought back.

The Premier League's upper reaches present a fascinating split. In this age of the leveraged buyout - of the toxic-debt threat and the ball-busting interest charge - City and Chelsea are monuments to generosity. It would be wiser not to call it philanthropy because both have strategic motives. But you can bet your car that Liverpool and Manchester United fans would prefer the model bequeathed by a Sheikh who sits on top of 9% of the world's oil reserves and by Chelsea's yacht-collecting sugar-papa. Liverpool, knocked out of the Carling Cup by Northampton Town and still paralysed by boardroom chaos, offer a particularly dismal counterpoint to the £120m lavished by Sheikh Mansour this summer on new players.

Abramovich set out at Chelsea in June 2003 in a stronger place because the team he bought were already on the edge of title challenges. His first really smart hire was a noncombatant: José Mourinho, who pushed Chelsea across the Rubicon of a first league title for 50 years. In his first season Abramovich lost £140m and there has been much bungling along the way. Interfering in Mourinho's work was the cardinal error that led to a long spell of managerial instability which ended only when Carlo Ancelotti showed himself to be a master at handling the unofficial Chelsea cabinet headed by John Terry.

For his £600m Abramovich has boughthimself three league titles, a trio of FA Cups and two Carling pots, plus a Champions League final. Not bad, in football's warped economics. City's owner, whose fortune was said during the takeover to be "many, many billions of dollars", has reached the Europa League so far. His is more of a bottom-up transformation, motivated, we assume, by the knowledge that Abu Dhabi's oil will run out in 90 years.

In the governing families of the United Arab Emirates, Sheikh Mansour is among those pushing for modernisation and diversification: hence the purchase, after 13 hours of talks with Thaksin Shinawatra in the seven-star Emirates Palace, of an institution who could not dispute the title of second biggest club in Manchester.

So what can Sheikh Mansour learn from Abramovich?

Chiefly, that without the right manager you're whistling Dixie. Only a handful of European coaches can manipulate a squad of 25 multimillionaires while coping with the prickly heat of expectation. Mourinho could, so could Guus Hiddink. Ancelotti brought realpolitik. The City job, though, has come too soon to another Italian, Roberto Mancini, a student impersonating a professor.

Sheikh Mansour's net spend on players is £300m and the annual wage bill will obliterate the £100m barrier in the next accounts. Against that background the owner must wince to see City take to the pitch with three defensive midfielders, or to hear the constant grumbling about the manager's training ground routines.

For Mancini to be shoved aside would not shock. The issue is whether the Sheikh's men were wise to appoint a young coach who made his breakthrough at a conservative club (Internazionale) in a more defensive league (Serie A) and expect him to adapt to the pinball tempo of the English game at a club where holding midfielders (Yaya Touré) can earn nearly £200,000 a week if all the clauses and incentives in their contracts are activated.

Abramovich and his Middle Eastern rival owe a debt, you could say, to Hicks, Gillett and the Glazers. Thanks to The Borrowers, few pause these days to consider the obscenity of the personal wealth behind City or Chelsea. Nah, forget that, the game's about to start.

This is comment. GNM does not necessarily support the views expressed.