By Andrew Mooney, Boston.com Correspondent

Joining the exodus from Fenway Park this offseason is another high-profile name, Jonathan Papelbon, who signed a four-year, $50 million contract with the Philadelphia Phillies. Much ink has already been spilled lamenting the loss of such a visible and effective cog in the Red Sox organization, and it is indeed a shame to lose a player who has consistently excelled in his role, as Pap has for the last six seasons. But if the Phillies were willing to throw that much money at him, by all means, let him walk. Paying Papelbon $50 million is just not good business.

The Red Sox already have a readily available substitute for Papelbon in Daniel Bard. Now, Bard may not be a perfect substitute for Papelbon –– exactly replacing his production –– but over the span of his young career, he’s been awfully close.

Jonathan Papelbon (2009-11)
194 G, 2.89 ERA, 199.1 IP, 10.79 SO/9, 0.7 HR/9, 3.85 SO/BB
Salary earned: $27,600,000

Daniel Bard (2009-11)
192 G, 2.88 ERA, 197.0 IP, 9.7 SO/9, 0.7 HR/9, 2.80 SO/BB
Salary earned: $1,199,189

Any advantage Papelbon maintains by his “big-game experience” or other intangible assets doesn’t justify an expenditure ten to 20 times greater, especially when that money could be allocated more efficiently to meet other, more pressing needs: a starting pitcher or a right fielder, for instance.

The gap in salary will only widen in the coming years, as the Phillies shower Papelbon, already in his 30s, with the riches of his new contract. The discrepancy in their performance, however, will not. In 26-year-old Bard, the Red Sox can give a pitcher in the midst of his prime the opportunity he deserves at an eminently affordable price. We’ll see if Papelbon can preserve the value of the Phillies’ investment when he loses a few miles per hour on his heater.

Admittedly, removing Bard from the set-up role leaves a void in an already suspect bullpen, particularly if Alfredo Aceves moves into the starting rotation. But adding lesser-known free agent relievers for the 7th and 8th innings is much more cost-effective than signing Heath Bell, former Phillies closer Ryan Madson, or any other big-name free agent closer. It certainly won’t cost $12.5 million per year.

In at least one respect, Papelbon is the gift that keeps on giving: pending the results of ongoing labor negotiations, his departure will likely provide the Sox with a compensatory first-round draft pick, valued at roughly $5-6 million, according to The Hardball Times. It could even yield the closer of the future: both Papelbon and Bard entered the league as early-round draft selections of the Red Sox.

In shipping down to Philadelphia, Papelbon himself proved to be a rational decision-maker: he took the money and split. Given that he didn’t bother negotiating with the Red Sox, it’s clear he wasn’t deriving much utility any longer from his time at Fenway. As for Sox fans, take heart: your team made a smart financial decision, though you may have thought it wasn’t possible. We’ll see how long the trend continues, but with his first major personnel change, new GM Ben Cherington may be setting the tone for his tenure at the helm of the Red Sox: strictly business.