The Twins have reportedly signed former Dodgers infielder Jamey Carroll to a 2-year, $7MM deal to be their everyday shortstop presumably for the next two seasons.
Terry Ryan took over the GM reigns from Bill Smith last week... so it's only fitting that his first move back in the GM chair is to sign an aging veteran infielder. While Ryan excelled in his first stint making major moves (trading AJ Pierzysnki, for example) he consistently struggled to bring in average to above average players to put around the Twins stars. Tony Batista and Livan Hernandez were two signings that looked awful at the time and even worse in hindsight; so the fact that the Twins targeted a 37-year-old infielder isn't that surprising.
Carroll isn't in the same class as Batista and Hernandez, mainly because he can still contribute. He hit .290/.357/.349 last season while playing 3B, SS, 2B and some outfield. The Twins reportedly will use Carroll as their everyday shortstop, though, and last season American League shortstops hit .266/.321/.386, which is basically the exact same offensive production Carroll gave the Dodgers.
Over his last four seasons, Carroll has hit .284/.362/.343, so at least offensively his production has been incredibly consistent. Now, he's 37-years-old and will be 38 before the season begins, so it's not out of the question his production falls off a cliff and he's a liability for the Twins over the length of the contract.
Defensively, Carroll has a reputation as a very good defender. Carroll has spent the majority of his time playing shortstop for the Dodgers, although the sample sizes are still not quite where you'd like them to be to get a good understanding of his defense from UZR/150. In 2010, Carroll's defense ranked as 4 runs above average over 150 games, but in 2011 it declined considerably to 6.2 runs BELOW average over 150 games. He played about the same innings each season, and the first assumption is that Carroll as a 37-year-old simply couldn't get to the same kinds of balls that 36-year-old Carroll could get to. That seems the most likely, in my opinion, but it's worth noting that UZR isn't a perfect defensive metric and players can fluctuate from year to year, so there's a chance Carroll could return to being an above average defender. If Carroll was 28 instead of 38, I would bet that he'd bounce back defensively, but his age is a serious concern.
Ultimately, the Carroll signing is an upgrade over what the team currently had, but I don't think it was the best choice. Signing anyone for two seasons when he will be 38 and 39 is almost never a good idea, unless it's Mariano Rivera, and even if Carroll's offensive numbers remain consistent, he's really only a net positive for the team if his defense returns to be at least average.
I still would have preferred Ramon Santiago, the utility man from Detroit, because his defense at shortstop is considerably better. His offense has actually been slightly better than Carrol's over the last four years (.266/.335/.374) although it's so close that offensively it really doesn't matter. As I've mentioned before, Santiago's defense at shortstop consistently rates as fantastic; in 2010, he played more innings at shortstop than Carroll and produced a UZR/150 of 16.4. That is ridiculously high. Brendan Ryan, widely considered the league's best defensive shortstop, played twice as many innings as Santiago did at shortstop in 2010, and posted a UZR/150 of 12.1. That led the league. Santiago only played about 125 innings at shortstop in 2011, so the sample size is definitely small, but he again posted a very good 10.4 UZR/150. He's also only 32-years-old, so a sharp decline in production is less likely than it is for Carroll.
Carroll has a shot to be a solid every day player, and his consistently good on base percentage will be an asset hitting second, but with almost no power and at least a chance of poor defense, I'm not a fan of the signing. Santiago will ultimately sign for less money and possibly less years, and he should outproduce Carroll, so it's frustrating to see the team consistently target the wrong players. Carroll isn't nearly the kind of mistake Batista or Hernandez were, but I think in two years we'll look at the signing and consider it a mistake. I hope I'm wrong.