When does a club know a player isn't worth the cash?

If Man. Utd meets Wes Brown's (6) asking price, how will that affect the wage demands of Nemanja Vidic and Wayne Rooney? Laurence Griffiths/Getty Images

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With no credible individual statistics, no public salary information, murky transfer dealings and no salary cap or luxury tax, soccer doesn't really lend itself to the kind of Moneyball principles of baseball and other sports.

Yet the fact is there are some basic do's and don'ts to transfer spending and managing a payroll. Ultimately, even without a salary cap, every club -- even if it's owned by Roman Abramovich -- has finite resources.

And therefore, it has to decide how it's going to allocate them. What's more, it has to do so knowing full well that its decisions have effects that could snowball.

Take Wes Brown at Manchester United as a case study. Brown recently turned down a new deal worth $4 million a year and reports suggest he's looking for around $6 million. He becomes a free agent this summer, which means he can sign with any other club on a free transfer. So what does United have to consider?

1. Is Brown worth more than $4 million a season in absolute terms?

Probably not. He's a serviceable defender, but no superstar. Had Gary Neville not gotten hurt, he'd be warming the bench. There are probably 20 right backs in the world better than Brown and most of them make less than $4 million.

2. So United is right not to budge from its offer? If he doesn't take it, it can just get somebody else, right?

Ahhh, there's the problem. Brown leaves on a free transfer, so if he goes, United won't get anything back. Which means it would need to find another right back who is as good as Brown (or better). And it would need to not only pay him a salary, it would need to buy him as well. Which could add up quickly.

3. How so?

Well, say United buys a mid-career right back of Brown's level. That would probably cost between $10 million and $15 million. Then you need to sort out the contract, which might be, say, a four-year deal worth at least $3 million, maybe more. You'd end up spending something like $22 million to $27 million over the next four seasons -- at that point you might be better off giving Brown that money.

4. So why doesn't United do that?

Well, there's a little something called the knock-on effect. United's left back, Patrice Evra, also wants a new deal. His contract expires in June 2009 and he would probably settle for $6 million a year. Unless, of course, he sees that Brown is getting that kind of money. At which point he might figure he deserves more, something like $8 million.

5. Is he that much better than Brown?

Probably. And Rio Ferdinand, whose deal also runs out in '09, might figure that he's more than twice as good as Brown (which, arguably, he is) and therefore deserves more than the $12 million for which he's supposedly angling (he's currently earning around $10 million a year). And if Rio gets that, then Wayne Rooney (currently around $8 million) might figure he should get more. As should Ferdinand's defensive partner, Nemanja Vidic, who just signed a deal for a comparatively measly $6 million.

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