Jonah Keri on the Red Sox Extending Dustin Pedroia

> Pedroia’s deal looks like a steal based on simple math. Since taking over the full-time second-base job in Boston in 2007, Pedroia has been a consistently above-average player. He’s netted at least three Wins Above Replacement in each full season of his career, with a high of 7.6 WAR in 2011 and an average of slightly less than five WAR per season. Pedroia turns 30 next month, and his new deal doesn’t kick in until 2015, when he’ll be 31 on Opening Day. Let’s be pessimistic and say Pedroia is a four-win player by 2015, then subtract half a win for each of the following six seasons, with him ending up a one-win player (a below-average regular or a bench player) in 2021, the year he turns 38. That would net Pedroia 17.5 WAR over the life of his contract. The current value of a win on the open market, based on recent free-agent prices, is about $6 million. That would make Pedroia worth $105 million over those seven years, producing a small profit on the $100 million the Red Sox will have spent. Even that math isn’t favorable enough to Boston. The combination of inflation and increasing industrywide revenues means we should expect salaries to rise, such that the cost of a win could be significantly higher than $6 million a few years down the road — which could make Pedroia an even bigger bargain.

Once again, Jonah Keri brings us good news about the Red Sox.