Are teams playing better defenders in left?

One popular notion in some sabermetric circles these days is that defense in the outfield corners is getting better, proof positive that teams are taking defense much more seriously. It’s an interesting theory, and fits with the preconceived notion that certain defensive metrics have descriptive value. Accept the data and you can accept the result.

That’s all easy enough to believe, especially if you want to discover a new trend, but what if the data isn’t reliably reflected across the various defensive metrics? And what if it flies in the face of what we see in terms of who it is that teams are actually playing in left field?

Consider who was playing in left field last season in the National League. To belabor the obvious, the NL doesn’t have the DH, so there’s an automatic incentive to take a defensive hit and get a bopper’s bat in the lineup from the position that winds up seeing fewer chances than infielders or center fielders do. Looking at everyone who played 500 or more innings in left last season, do these sound like the “better fielders” that have been advertised?

Not that there’s a direct-causal relationship, but it’s more than a little amusing to note that three of the league’s playoff teams last year were starting Burrell, Ibanez, and Gomes -- players not usually associated with their defensive contributions, and three guys who have had to spend good chunks of time as designated hitters after moving away from their initial positions as prospects.

Admittedly, the outfielders who stayed as outfielders make for an interesting crew. Milledge, Parra, Smith, Tabata and Bay all got chances as center fielders early on in their careers, either in the minors or even briefly in the majors. But none of them were ever expected to stick in center and were corner-bound early on. They’re also not all good outfielders, mind you; Bay hasn’t graded out as any better than mediocre in any of several venues via several metrics. But Parra, Holliday and Tabata all offer positive value afield, and Parra and Tabata are recent enough arrivals to represent some form of validation for a “recent defensive improvement” theory.

Among the ex-infielders, Braun, however athletic he was as a college shortstop once upon a time, proved to be a bad third baseman, had a rough first year in left in 2008, but seems to have become a better left fielder in the past season-plus, at least according to Total Zone, Plus/Minus and Fielding Runs.

It’s everyone else where you start running into problems. Ibanez, Lee and Soriano would probably be DHs in the AL if their contracts didn’t keep them planted in left field for their respective ballclubs. All three provide awful defense. Willingham grades reliably poorly, as does Gomes. Morrison is a big galoot and giving left field his best shot, but it would be hard to call him an obvious success. If you want to be generous, you can compare his move to left to Willingham’s, or perhaps to the Rockies’ success with their decision to move Brad Hawpe to right field to get his bat in the lineup earlier in the decade. That was a defensive hit the Rockies were willing to take for the offensive boost; it was an idea that helped get them a pennant, but that doesn’t sound much like a better brand of defense getting played in the outfield.

If you want to get really skeptical about the data, you might note that Burrell has done extremely well for the Giants according to several metrics, which probably seems strange after three bad years in left for the Phillies, which preceded the Rays’ signing him to DH. To my way of thinking, that just goes toward how much confidence we can invest in any interpretive defensive metric -- the information is suggestive, but not conclusive. What is incontrovertible is that one of the so-called “smart” teams, the Rays, as performance analysis-aided as anybody in the industry, took one look at Burrell and said “DH.” Does this mean the Rays were dumb? Of course it doesn’t, especially when the Rays get -- and deserve -- credit for doing so much to improve their defense between 2007 and 2008 to aid their massive turnaround as a franchise.

So, maybe things changed for the better in 2011, right? Coghlan moved to center, while Milledge moved to the International League. You can add Ryan Ludwick of the Padres to the latest list of regulars -- he fits into the outfielders-playing-outfield group, and does it well. The Braves moved Martin Prado out of the infield because of his bad glove; according to Total Zone and Fielding Runs he remains a liability as a left fielder, while UZR and Plus/Minus think he’s just fine out there. That doesn’t sound conclusive one way or another, but it’s early yet. Maybe he’ll be the next Braun, or the next Soriano.

In the absence of any compelling trend, what might be especially interesting is that for all the talk of improvement, one thing has been damnably consistent over the past decade. Per Baseball-Reference.com, in 1990, left fielders were catching 48 percent of all fly balls. In 2000, they were catching 47 percent of all fly balls, and in 2009 they were catching 47 percent of all fly balls. Last year, with all this improving going on, left fielders caught 46 percent of all fly balls hit in their direction. So far this year it’s at 49 percent. And all of this while there are fewer balls in play as the strikeout rates keep going higher. Maybe it’s just me, but maybe the teams like the Giants and Reds and Phillies and Marlins, and perhaps now the Braves, have gone for a bat in left field, maybe they’re the ones onto something elegant and classic: putting boppers in a bopper’s slot.