The Red Sox sent Marco Scutaro to the Rockies in exchange for pitcher Clayton Mortensen on Saturday night. This was a move meant to open up some financial flexibility for Boston, possibly to sign someone like Roy Oswalt to fill one of the rotation's remaining contested spots. Mortensen might be something, but he also might be nothing -- his path isn't all too clear at this point.
All of that -- Mortensen's future, what the Red Sox do with the freed up money -- is something we'll see play out, and likely soon. It's not entirely clear how either of those things will work out just yet, even if we can guess about them.
What is clear is who the Red Sox still have to play shortstop for them, now that both Scutaro and Jed Lowrie have been shipped off to the National League. The Red Sox still have Mike Aviles, acquired from the Royals for Yamaico Navarro at the 2011 trade deadline, and Nick Punto, signed immediately after Lowrie was dealt, available to play shortstop.
Punto is a fine defensive shortstop. Baseball Prospectus's Fielding Runs Above Average lists him as being worth about a win on defense over the last few years, despite not playing full time over those seasons. Baseball-Reference's defensive wins above replacement say the same thing, and UZR goes as far to say as he's been worth two wins over the same stretch. None of those metrics are gospel -- we haven't figured defense out to that degree -- but it's probably a good sign when the numbers agree with the conventional wisdom surrounding Punto's glove work.
What Punto is not is a fine hitter. He's not awful, by any means, assuming he sticks at shortstop. He's hit .254/.340/.335 since 2008 (1,271 plate appearances); worse than the average shortstop, but not by a ton. True Average, an all-encompassing offensive statistic that accounts for park, league difficulty, and basically any other context you can think of, lists Punto at .247 over the last four years. Shortstops were at .253 last year as a unit, meaning Punto isn't that far off from that level, and has a glove to make up for the difference.
This is why, even with the FRAA figures that are less optimistic than, say, UZR, Punto comes out to something like a two-win player over the course of 600 plate appearances (he has 4.6 WARP over his last 1,271 PA). While WARP (or any wins above replacement stat) isn't predictive, the rate at which Punto's produced at over the last four years is that of, for all intents and purposes, an average player. Scutaro has been better than that by about a win per year, assuming the same kind of usage for both players, but Punto isn't in this alone at short.
Aviles doesn't have the glove of Punto, but he can hit. He is a career .288/.318/.419 hitter over 1,325 plate appearances, with all but the last 107 of those coming in a pitcher-friendly environment. His line is also dragged down a bit by playing through an elbow injury that eventually required Tommy John surgery in 2009, but more importantly, facing right-handers has caused some trouble for him, too: he has a career line of .283/.307/.396 against righties, whereas he has performed much better against southpaws (.299/.344/.470, and a multi-year TAv of .302).
Punto has the glove, and a bat best described as tolerable. Aviles can mash lefties, but owns a glove you could equate with the bat of Punto. Neither of these players is in danger of replacing Scutaro's production by themselves, but put together in one platoon or another -- whether by handedness of the opposing pitcher or the tendencies of Boston's own hurlers -- and the Red Sox have themselves something here that can work as a facsimile of Scutaro's expected 2012 contributions.
Punto's glove makes him valuable at short when one of the Red Sox more contact-oriented pitchers is on the mound. Clay Buchholz, Alfredo Aceves, Aaron Cook assuming he makes the team -- pitchers like that aren't going to miss a lot of bats, but will induce grounders and balls in play to get their outs. Punto gives those pitchers a better chance of success than they would have without him, and on the side of the infield that will also likely feature the now below-average glove of Kevin Youkilis. Punto also has no discernible lefty or righty split -- he's a little better against southpaws, but the difference is barely noticeable, so he doesn't need to be lifted for a pinch-hitter in a game with a close lead where defense might be more appreciated than offense.
Aviles' bat and lefty-mashing tendencies make him a useful piece off the bench in the late innings, but also a capable option to man shortstop against the left-handed starters of the league. Against righties, he isn't great, but he's been better against them than Punto over the years, so he can hold his own if the Red Sox need offense more than defense late in a game started by Aviles. He's also the perfect kind of Fenway player, with more doubles and triples power than pure home run pop.
Both of these players represent tactical options for new manager Bobby Valentine. Put together, the Red Sox should be able to squeeze two or three wins out of the shortstop position, less, but not a whole lot less than they have the last few years when Scutaro and Lowrie took turns being productive or injured. Punto and Aviles, who have their own history of health issues, are likely to continue that particular Red Sox shortstop trend as well, but as both are nearly capable of holding this spot on their own, a short-term injury shouldn't be a season-changing issue.
The Red Sox might have downgraded slightly in their shortstop production by trading Scutaro, but Aviles and Punto combine to form something pretty close to what Scutaro would likely have done. If the Red Sox use the money freed up by the deal to add another quality starting pitcher, then the rotation, bullpen, and the organization's pitching depth will have improved, making the 2012 Red Sox a better team than they were before the Scutaro deal.
In the end, the chance to field a better team is what matters. Scutaro was useful and productive in his two years in town, but with the Red Sox clearly attempting to avoid the luxury tax as much as possible over the next two seasons, he and the money owed to him were trade-able. The inexpensive replacements on hand give the Red Sox the opportunity to improve not just a rotation that could use another arm, but the margins as well -- after 2011, we should all know how important squeezing an extra win or two out of the margins is.