Borussia won the European Cup in 1997 but seven years later they were on skid row and could not pay their players

The dry run for the Champions League final takes place at the Westfalenstadion on Saturday: Borussia Dortmund versus Bayern Munich, two old rivals winding down the Bundesliga season while preparing for an event that at one time would barely have seemed credible bearing in mind the background to this story.

Imagine, if you like, Manchester United bailing out Leeds United with an emergency loan back in those days when the Yorkshire side found themselves in the spiral of financial hardship that threatened their entire existence.

Or another wealthy, powerful Premier League team sending a seven-figure cheque to Portsmouth or any of those other clubs who know what it is like to be bucket-collection skint.

In England it never tends to happen. The rich get richer and the poor rattle their tins. In Germany, they appear to have a more generous streak bearing in mind it was Bayern's intervention, with a €2m loan, that helped Dortmund keep afloat during those desperate times in 2004 when they could not even afford to pay their players' salaries.

Without that money, would Dortmund have embarked on the uphill climb that has brought them to the final? Ask that question to Die Schwarzgelben and they will argue that, yes, their success story has other origins and the financial help from Bayern should be only in the small print of their story.

It is no wonder they do not particularly want to dwell on it but it does add another twist to what takes place at Wembley on 25 May. At the very least, Dortmund have clear reason to be grateful to their opponents.

Nor is it the only time Bayern have acknowledged their position as the richest club in Germany by making handouts to financially troubled clubs. They have previously helped 1860 Munich and FC St Pauli. Dortmund's position, however, was the most severe, riddled with debts and on the verge of bankruptcy after years of extravagant spending and a plunge in share prices.

"It was a critical situation for Borussia Dortmund," Uli Hoeness, Bayern's president, has said. "When they couldn't even pay their salaries we thought we should help. I'm a big fan of tradition in sport and I think it was the right thing to do."

The loan was interest free and Bayern agreed a schedule whereby Dortmund had nine months, until June 2005, to pay it back in full. The first €1.5m came back after two months; the rest of it later.

Remarkably, it was not revealed until early last year, when Hoeness brought it up at a supporters' meeting. With the two clubs embroiled in a title race at the time, there were allegations in the German media that he had revealed it to undermine Dortmund. Yet Jupp Heynckes argued that was unfair in the extreme. "It was a good few years ago and I think it's a positive thing there is some solidarity in the league," the Bayern coach said.

Of course, the precise significance of that money can never be measured and, perhaps not wanting to give Bayern too much credit, there has been at least one occasion when Dortmund officials have tried to play down its relevance in the greater scheme of things.

Thomas Tress, Dortmund's chief financial officer, once pointed out that it was a relatively small amount given the size of their debt.

"First of all it was very honourable from Bayern Munich, helping other clubs in critical situations," he told SportsPro. "It was a critical situation for Borussia Dortmund. But it was not to save Borussia Dortmund because we are talking about €2m. If you realise the financial debt was roughly €200m, so €2m does not solve the whole problem, but it helped. It was an honourable step and what's more to say?"