1. The Red Sox shortstops were so horrendous last year that there is a massive amount of room for improvement on a 95 win team.
2. The money isn't exorbitant, and equally important, the contract is short.
3. Despite Scutaro being a Type A free agent, the Red Sox gained picks overall and actually moved up in the first round, barring a major move in free agency by the Braves.
I knew the Red Sox were a disaster at shortstop, but I didn't realize just how bad the overall numbers were until the Globe showed the composite numbers. Red Sox shortstops put up an unbelievably bad line, .235/.297/.358, good for 26th, 25th, and 20th for major league teams at the position. Using a nifty tool from Baseball Musings we can calculate the expected runs scored for the Red Sox. For simplicity's sake, I'm using 2009 stats and the lineup from the end of the season when healthy - V-Mart at catcher, Bay still in left field, and Lowell at 3B, as well as the aggregate shortstop output. This lineup is predicted to score 5.791 runs per game, or a total 938 runs. This is well above the actual runs scored thanks to injuries and days off, but for comparative purposes is useful. Now, what happens if Scutaro were in the lineup instead?
Again, this isn't a prediction for next year, but let's say that Scutaro put up his rather underwhelming current career averages (.265/.337/.384) instead of the aggregate numbers the Red Sox shortstops put up. This would results in a lineup that scores 5.901 runs per game for a total of 956 runs, a difference of 18 runs. Despite the fact that Scutaro has been well below average offensively for his career, his addition to the Red Sox at shortstop would still be a two win improvement offensively. Normally, two win improvements aren't that easy to come by. Using Scutaro's actual 2009 numbers (.282/.379/.407) would result in a 36 run improvement in the offense, or 3.5 wins. As a point of comparison, this improvement is on par with replacing Kevin Youkilis with by far and away the best hitter in baseball, Albert Pujols.
As far as the numbers go, the value of a win depends on who you want to believe and where your team is in the standings. According to revenue work done by a variety of folks, the more a single win makes a difference in your playoff odds, the more valuable they are. For a team like the Pirates, an additional win or five isn't going to make a difference in terms of revenues. This holds true on the high side too - as a playoff spot becomes more and more likely, the value of one additional win decreases. Circa 2007 a 90 win team would earn $3.5 million for one additional win, the highest observed. Fangraphs took a look at things from the free agent market perspective, and showed that for 2008 a marginal win cost $4.5 million. Either way, a 3.5 win improvement is well worth the $6 million / year the Red Sox have committed to Scutaro.
Also, because the contract can be a two year deal it is hard for the Red Sox to have lots of dead money in the deal. If Scutaro flops or Lowrie hits like Theo thinks he can, then the Sox have the financial resources to float a $6 million dollar (utility) man. Thanks to the short contract length the Sox will never be in a Julio Lugo or Edgar Renteria situation, desperately looking to move a player, even if they have to pay half of the remaining contract to do so.
Finally, the Scutaro signing doesn't hurt the farm system very much. Thanks to Billy Wagner signing with the Braves, the Red Sox get the Braves 1st round pick (19th overall) as well as a sandwich round pick.
A sandwich round aside - if you're familiar with it already you can skip the italics. The sandwich round is a bit of an oddity - it exists between the first and second rounds, and can be of varying sizes depending on the number of free agents that sign with other teams. It might be easiest to think of it as the 1.5 round of the draft.
In exchange for Scutaro, the Blue Jays get the Red Sox first round pick (29th overall), so with this exchange they've actually moved up in the standings AND gained a pick. To top it all off, if the Red Sox sign another Type A free agent, John Lackey or Matt Holliday for example, the Red Sox would give up their 2nd round pick and not the compensatory pick from the Braves. However, they could gain another team's 1st round pick as compensation for Jason Bay, as well as another sandwich round pick. If everything breaks just right for the draft, for example, if Bay signs with the Mariners, the Sox could swap Scutaro and Holliday into their lineup in exchange for their first and second round draft picks, while gaining Atlanta and Seattle's first round pick and two sandwich round picks. Those later draft picks are great opportunities to snag players who fall because of signability concerns or lower upside arms that can move quickly through the system. For example, Nick Hagadone and Bryan Price, two of the three prospects in the Victor Martinez deal, were sandwich round picks in 2007 and 2008.