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When Rangers play Celtic on Sunday it will be an almighty collision between two juggernauts travelling in reverse.
The Old Firm match at Ibrox amounts to a title decider and this season will be the 20th consecutive year in which one of the two clubs will be crowned as Scotland's champions. For the foreseeable future their domestic stranglehold will continue, but their power evaporates as soon as they pass Hadrian's Wall.
The resumption of the Uefa competitions next week will be a source of discomfort in Glasgow. Both clubs have a turnover, salary budget and support base on a far grander scale than those of PSV Eindhoven, CSKA Moscow or AZ Alkmaar, but those are the sides still involved alongside the more traditional heavyweights in the semi-finals of the Champions League and Uefa Cup.
Rangers and Celtic bleat that Scottish football's meagre broadcasting income gives them an insurmountable hurdle when it comes to competing with Europe's best, but the achievements of the Dutch and the Russians mock their complaints.
This year's Scotland Premier League race has been gripping because the two Glasgow clubs have been evenly matched. Only once in recent seasons - in 2002-03, when Rangers won the title by goal difference on the final weekend - has the championship been so keenly contested. Celtic hold a two-point advantage going into Sunday's final derby and after that each club will have only four matches left.
Celtic won the championship by 17 points last season, but a combination of their deterioration and the improvement in a revamped Rangers has resulted in the current race being virtually neck-and-neck all along.
Celtic have had cause to mourn the departure last summer of their peerless striker Henrik Larsson. His former team-mate John Hartson has replaced him as Scotland's leading goalscorer but Larsson was Celtic's only player of truly international renown.
Without him it is impossible to imagine the club returning to the heights of 2002-03, when Liverpool and Blackburn Rovers were among their victims en route to a Uefa Cup final against José Mourinho's Porto in Seville. Celtic lost, and two years on that match can be seen as a high watermark rather than a springboard.
This season Celtic were placed in an unforgiving Champions League pool along with AC Milan, Barcelona and Shakhtar Donetsk, but it was revealing that without Larsson their points total - five - was lower than they had managed in any previous group campaign.
There was no reason for Rangers to gloat. They did not reach the group stage at all, having been eliminated in a qualifying round by CSKA Moscow, and in the new-look Uefa Cup section they pulled off the extraordinary feat of failing to finish in the top three of a five-strong group that also contained AZ Alkmaar, Auxerre, Grazer AK and the unknown Polish side Amica Wronki. Not since 1992-93 have Rangers made a meaningful impression in Europe.
Despite attracting two of the highest average attendances in Europe - Celtic fill their 60,000 seats at Park- head, Rangers their 50,000 at Ibrox - the Old Firm are slipping further from the mainstream. Over several years they each ran up sizeable debts by paying English Premiership-level wages without Premiership-level broadcasting income. With their ambitions to move to the Premiership being no more than a pipedream, those heady days are over.
Jean-Alain Boumsong was a shrewd signing on a "Bosman" transfer but it was humbling for Rangers to have to sell him only five months later because Newcastle offered £8m. Rangers, once the cash cow for agents all over Europe, now have only three players who earn more than £20,000 a week.
Celtic's directors are under immense pressure to finance the £5m fee and £45,000-a-week wages that would convert Craig Bellamy's successful loan deal into a permanent transfer from Newcastle. To do so would exhaust their resources and leave no more funds for manager Martin O'Neill to replenish an ageing side. O'Neill, the club's most coveted asset, has made a series of veiled criticisms about the lack of available funds.
Two years ago in Seville he and Mourinho were only a few yards apart in the dug-outs. Since then the brakes have been applied to Glasgow's clubs. Mourinho and the rest have accelerated away from the Old Firm.