When Tony Copsey walked into the dressing room at Stradey Park and met his fellow second-row forward Phil Davies in 1989, he could hardly have imagined that 13 years on they would face each other in the most costly relegation match British rugby has seen.

The Stoop is a perfectly named venue for this relegation decider. One team will win and prosper, the other - unless the RFU or freak results intervene - will have to buckle under the financial catastrophe of a forced exit from the Premiership and all the riches it carries with it.

Leaving aside the committee-room debate as to whether Rotherham should be allowed to come up to the Premiership - to be resolved next week - such situations test friendships.

Copsey, now Harlequins' managing director, was planning to ring his friend, who is director of rugby at Leeds, the opposition, and "give him some abuse" last night. But he cannot bring himself to wish ill on someone he rates highly.

"He's a fantastic guy who has done a tremendous job at Leeds. I've got the utmost respect for him. I think Leeds have brought a lot to the league this year, on and off the field. They've been part of Premier Rugby, unlike Rotherham when they were up."

The effects of relegation barely bear thinking about. According to Copsey, about half of their backroom staff of 20 would lose their jobs and there would be hefty pay-cuts for any players willing to stay. For Bath and Saracens, who mathematically are still in danger themselves, a similarly doom-laden scenario would apply.

To quote Saracens' owner Nigel Wray, relegation is a "smoking gun" for those trying to nurture English club rugby, capable of reducing the healthiest business to its knees. It explains why the top clubs are still scrabbling to avoid the drop by political means, thus denying Rotherham their hard-earned promotion slot. Never mind that "ring-fencing" the Premiership so late in the season would be ruinous for English club rugby's credibility; desperate people clinging to a precipice will do anything to hang on.

Davies echoes Copsey's sentiments. "We've been pals for a long time. He's a good man, I enjoyed playing with him and he's done a marvellous job for Quins.

"Of course I'd feel sorry for Tony if they went down. I felt for Quins last Friday night when they conceded a late try against Wasps and missed out on a bonus point. I've had a few of those experiences myself and they're not very nice."

Personal relationships aside, though, Davies sounds the more sanguine as the crunch looms. He even supports the concept of relegation, despite Leeds's predicament. "If someone had offered me this position at the start of the season I would have taken it," he insists. "We were looking at the table last night and a five-point win as we presently sit would put us up to ninth. That's the way we're looking at it."

Davies, correctly, suspects Quins are under more external strain than his own team, who have Chris Murphy back in the second row after suspension. "Because they're the big club with all those Test stars there is a fair amount of pressure on them. If we get relegated, I'd expect things to stay very much as they are. No one expected us to do anything, so anything we achieve from now on is a bonus. Our off-field structure is pretty lean and mean."

The consequences would be worse at Quins, as Copsey admits. "The mood is very positive but we're in this eye-of-the-storm situation. Normally we'd be planning for next year but, as we're not sure what our future holds, we're twiddling our thumbs a bit. We're in limbo and the Leeds game, to be honest, can't come soon enough.

"Relegation would be devastating in terms of turnover and revenue. Business has never been better; average gates this season have been over 7,000 compared to 3,900 last year. All that growth is there to see. If the pressure doesn't get to them, hopefully Friday will be the day the team start performing to their potential."

The good news for Quins, whose fly-half Paul Burke has recovered from ankle trouble, is that tonight's game is a sell-out, proving that vultures will pay good money for a fresh carcass.

Leeds, even if they lose, will still have two more games to wriggle above Bath but their hosts have only one remaining away fixture, at Sale. That old image of Harlequins as cravat-wearing playboys is a tired cliche, but they would be unwise to rely on many favours from their friends in the north.

· Harlequins are advising ticketless supporters not to turn up; the game is sold out.

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