If you follow prospects, you're probably hearing positive things about Kris Bryant, one of the Cubs' many high-impact pieces. Bryant, in admittedly small samples, has absolutely crushed the ball in his professional debut this year. The stats are phenomenal: a 209 wRC+ in Low-A, a 212 wRC+ in High-A, and a 214 wRC+ in the Arizona Fall League en route to an MVP award. Scouts rave at his power, and he's looking like a middle-of-the-order bat sooner rather than later.
If you follow Bryant, you've also probably heard quite a bit about his position -- or rather lack thereof. Bryant is a third baseman, at least for now, but there are questions about his glove. In 2012, Matt Garrioch shared concerns about Bryant's ability to handle third -- similar concerns to what I've heard from most talent evaluators. Most think that he'll wind up in an outfield corner or at first base sooner rather than later, as his lateral quickness doesn't exactly remind anyone of Manny Machado.
There are two ends of the defensive spectrum in stark relief these days: there are leather wizards at third like Machado, Evan Longoria, and Adrian Beltre -- and there are guys like Miguel Cabrera and David Freese, who really don't succeed as defensive third basemen.
Nevertheless, teams are succeeding -- look at Cabrera and Freese's 2013 teams for example -- despite having sub-par defenders at third. It's enough to make you wonder -- how valuable is it, really, to have an excellent defensive third baseman?
The simplest way to start to identify a player's defensive value is to go to one of the advanced defensive metrics -- you've got UZR, DRS, and FRAA as the "big" three. These numbers give us a run value, sure, but these numbers aren't stable or terribly reliable. They're a nice shorthand, but there's research that these aren't terribly accurate over short samples (even as much as two to three years), so we might need a slightly better way to measure the value of a defensive contribution.
In the meantime, I want to try and see if the defensive role of the third baseman is changing -- or if the way the game is shifting* will change how important third base defense is.
* - Foreshadowing!
There's been a lot of talk about how we've entered a new run environment in baseball -- one that's different from the mid-00's and quite different from the "steroid era." Since 2004, strikeouts are way up across baseball, and pitching rate stats are down. Teams are scoring fewer runs, and, if I'm not mistaken, putting fewer balls in play.
You'd expect that to mean that chances for third basemen might be down as well. Fortunately, we can check this.
data courtesy of Baseball-Reference
So, let me share a few things about this table. "PA" is plate appearances, and "RHB%" is the percentage of those plate appearances where the team was facing a right-handed batter. This is important because right-handed hitters are probably a little more likely to pull the ball in the direction of the third baseman. "BIP%" is the percentage of balls in play during all of those plate appearances ... and as you can see, that number is dropping, albeit in a small way, over the last ten seasons. I threw "GBIP%" or ground balls in play percentage in there just as kind of something interesting ... it hasn't changed much during the time period of this study.
Alright, so now we get to the good stuff. "FLD" is the number of balls fielded by any third baseman during the season. The numbers by themselves show a very small decline from the mid-00's to today. "FLD2O" is the percentage of those balls fielded that were turned into outs, a number that's remained fairly static over time. The last column, "FLD/PA%" is where I calculated the percentage of balls fielded by the third baseman as compared to the total plate appearances during the season.
This FLD/PA% is slowly dropping ... and it's dropping a bit slower than I would've anticipated. If balls in play are down two percent (ish) since 2004, I'd expect -- rightly or wrongly -- that the number of balls fielded by third basemen would have diminished more. There's a chance that some of the difference is being made up by increased use of the shift, where third basemen are positioned further to the right of the batter to compensate for pull-heavy left-handed hitters. As shifts have become more and more common -- and in some cases, more extreme -- perhaps this affects how many chances a third baseman gets ... giving him more chances to field a ball than he would normally, if he were locked down on/near the third base bag.
Another thing worth examining is that the raw balls fielded data is probably pulled down by poor-fielding third sackers, and pulled up by slick-fielding ones. I'd think this would be a wash over the course of the entire league, but perhaps it's not -- we'd probably need to dive into the data further to find that out. There's a non-zero chance that third basemen as a whole are becoming more -- or less -- able to field their positions.
League-wide, it appears that there is a shift to fewer balls in play, and it appears to indicate fewer chances for third basemen -- but that it's not a tremendous shift. If all players are seeing perhaps a two percent decrease in balls in play, while the ground ball and right-handed hitter percentages staying close to steady, then the proportional amount of chances for third basemen looks like a very small decrease, especially taking the increased use of the infield shift into account.
Perhaps then, third base defense is about as important as ever ... as a league-wide rule. Perhaps the real difference is for particular teams, and their styles of play -- and that's something to explore further in the next week or two. For now, I think it's important to recognize that on the macro level, third base defense is only slightly less important than it might have been ten years ago, and that Kris Bryant will want to improve his glovework if he wants to stick at such a premium position.
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Bryan Grosnick is the Managing Editor of Beyond the Box Score. You can follow him on Twitter at @bgrosnick.