We're sure that you've already heard plenty about how MLB teams have been placing an increased emphasis on defense of late. This is due in part to a revolution in defensive evaluation: as more and more batted ball data emerges, defensive statistics have become increasingly useful and accurate, and teams have been able to reap the benefits. The Rays became the poster child for this movement after they essentially reversed their record from a last-place 66-96 to a pennant-winning 97-65. While this was not due entirely to defense, one of the major changes that ownership brought about was to place the emphasis on defense that saw them rise from a third-worst -6.5 UZR/150 in 2007 to 2nd-best 11.0 in 2008 (it also seems worth mentioning that the only team better was the Phillies, at 14.8, and we all know how that ended).
That said, let's take a look at who's shown the biggest improvements on defense this season. We're going to use FanGraphs' UZR/150 as our quick and dirty stat, though we admit that it has its flaws, as does any defensive metric. In any event, who's pulled a Tampa this season?
One general note: it's interesting that so many of the teams that were near the bottom of the pack in '08 showed the greatest improvements in '09. There's two ways to look at this development. Optimistically, you could say that the front offices of these teams are smart, recognized that they could stand to improve on defense, then took steps to correct the problem. Or, we guess you could just point out that since they started low, they had nowhere to go but up. To which we say: you a dark, dark person.
In any event, the top of the list isn't very surprising. Detroit, Seattle, and Texas are three teams that everyone knew was making a newfound commitment to defense. The Tigers brought in Adam Everett and haven't had to suffer Carlos Guillen and Miguel Cabrera's defensive stylings. Franklin Gutierrez, Endy Chavez, and Ichiro make up the best defensive outfield in the game, and Adrian Beltre is no slouch. Even the Rangers have talked all season about making a commitment to defense, perhaps best evidenced by their willingness to rush glove wizard SS Elvis Andrus to the bigs at the tender age of 20. But we'd never have guessed about the Reds and Pirates. What happened there?
In Cincinnati, they've got an outfield that is similar to the Mariners' group in terms of defensive excellence. Among guys with 300 innings, Drew Stubbs, Willy Taveras, Jay Bruce, and Laynce Nix have been flat out excellent. They've only got three guys posting negative ratings, and Edwin Encarnacion's -17.2 is now Toronto's problem. Plus, Joey Votto (-1.3 at 1st base) and Adam Rosales (-0.9 at 3rd) are hardly huge liabilities. This is an overall solid group that, if they could hit and/or pitch, would be great.
There's a different story out in the Burgh, though. Their two best defenders, Nyjer Morgan (+24.1) (!) and Jack Wilson (+17) are gone, and they've got serious defensive holes with 2B Delwyn Young, SS Ronny Cedeno, and RF Garrett Jones. This is a case where you see the leftover contributions of the dearly departed having an unfairly positive effect on the team as a whole.
So after that negative note, let's take a look at the bottom part of this chart. The Mets really stand out, as they've gone from pretty good to abysmal. However, even we can't hold them fully responsible for this drastic defensive decline; after all, as has been the case with every other facet of their season, the amount of injuries they've suffered has greatly affected their ability to play with their desired alignments. It's not their fault, for example, that Anderson Hernandez and Alex Cora have played a lot of shortstop. But some of their guys really are just outright bad defenders (see: Wright, David; Sheffield, Gary; Castillo, Luis; Francoeur, Jeff (ha!)). So this ranking is not entirely undeserved.
The Phillies have regressed quite a bit, but it can be hard to maintain the level of excellence that they established last season. For what it's worth, the entire roster of regulars (300+ innings) is basically solid but unspectacular at defense; Chase Utley leads the club with a +8.7 mark, and Shane Victorino is the only subzero straggler, with a -3.8 rating.
For people that are searching for reasons as to why the Cubs have disappointed this year, one to point to could be their defensive shortcomings. Milton Bradley was pretty bad in the outfield - we know, Milton, we're singling you out and there's a negative atmosphere in this blog, but you're a DH in the NL - but not nearly as bad as Alfonso Soriano, who's been one of the worst left fielders in the game. Jake Fox has seen too much time at third base, but Aramis Ramirez is no great shakes with the glove himself, and Mike Fontenot hasn't contributed much in the way of...well, anything, really, but he's been really bad at defense. Guy's got a great baseball card, though.
So what do we take away from all of this? Well, improving defense isn't guaranteed to make you a contender, but it's an effective, affordable way to upgrade your club. Or at least it was affordable; as it becomes a more valued, quantifiable skill, teams are going to pay more for premium defenders. It's the Moneyball concept: teams could win on the cheap by identifying inefficiencies in the player market and exploiting them. For a few years, that inefficiency was OBP; of late, it's defense. But as teams start paying and playing guys like Adam Everett, Elvis Andrus, Endy Chavez and Adam Dunn (still paying attention?) who are offensive zeros but save enough runs to be valuable, it's going to be time to find another inefficiency. Our prediction? Soon you'll be hearing about how the Rays/Rangers/Other Upstart Team have been great because all their hitters are otherworldly bunters. That'll be a fun couple of seasons.