Stanton, Altuve, and Another Warning About Defense

Over the last calendar year, there are 139 qualified major-league hitters. Prorating their plate appearances to 600 per person, one finds that Mike Trout has the highest WAR at 7.2, followed by Russell Martin, Buster Posey, and Anthony Rizzo. None of that should come as much of a surprise, but the hitter right behind that group and just ahead of Josh Donaldson, Andrew McCutchen and Bryce Harper could provide a bit of shock. Over the last calendar year, Kevin Kiermaier has been worth six wins per 600 plate appearances.

Kiermaier, who has worked to improve his offense, is incredibly reliant on his fantastic defense for his great WAR numbers. While Kiermaier is a valuable player, it is possible that his WAR total is inflated by defensive numbers that are likely to come down over time. Kiermaier has logged roughly 1200 innings in the outfield and has a UZR/150 of 42.1, but only six active outfielders with at least 2,500 innings have a UZR/150 greater than 15, with Lorenzo Cain, Ben Zobrist, Peter Bourjos, Brett Gardner, Josh Reddick, and Jason Heyward falling between 16 and 22 — that is, roughly half Kiermaier’s current rate. Although he’s been good, Kiermaier is probably not the fifth-best player in baseball over the last year, and his defensive numbers should serve as a reminder that defensive statistics take some time before they become reliable.

Yesterday, I covered some players whose current WAR was potentially undervalued due to lower than normal defensive numbers in an article titled Heyward, Pedroia, and Your Annual Reminder About Defense. The present article renders yesterday’s title false as the articles together are now daily reminders, but this post should be the final one in this series with few, if any, more reminders coming in the near future. The caveat regarding small sample size from Mitchel Lichtman and our FanGraphs library is quoted more fully in yesterday’s piece, but to summarize: use three seasons of UZR when being conclusory about the defensive talent of any given player.

Today’s post focuses on those players who might be overvalued by looking at current season WAR numbers due to a large increase of defensive value compared to the previous three seasons. Like yesterday:

I looked at only those players who were qualified hitters from 2012 to 2014, who did not change positions, and who are also qualified this season.
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I took the three-year defensive runs, divided by three to get to one year, and then divided by three again (also called dividing by nine), as we are one-third of the way through this season. I compared that number to the current season’s defensive-runs number.

The following players had the largest gap between this year’s defensive numbers and their numbers over the previous three seasons.

Giancarlo Stanton

Stanton is having a fine season at the plate with 19 home runs, and his current 134 wRC+ is below last year’s 159 mark owing mostly to a .275 BABIP that’s more than 50 points below his career average. In the field, Stanton’s UZR has been very close to average over the past three years and his entire career, but this year his numbers top all right fielders. Stanton is likely on his way to another six-win season, but we should expect that much more of his value at the end of the season will come from his bat and not his glove.

Dexter Fowler

After spending the early part of his career in Colorado, Fowler is now playing for his third team in three years. He escaped the spacious center fields of the Rockies and the Astros’ home parks to the more manageable Wrigley Field. Fowler has always rated as a poor center fielder by both UZR and DRS, but this season, he’s been just above average by UZR. Fowler has been roughly average with the bat, giving him one win on the season thus far, but that number might inflate his actual value to the Cubs.

Asdrubal Cabrera

Cabrera has been close to an average baseball player over the past three season despite playing a pretty poor shortstop. The positional adjustment along with average offense has resulted in about five wins above replacement from 2012 to 2014. Cabrera’s bat has not been there for him yet this season, hitting .203/.261/.302, but good defensive numbers have kept him barely above replacement overall with his current WAR. If Cabrera cannot get his bat going, he is likely a below replacement-level player even if he moves to second base permanently after a small test-run last season.

Jose Altuve

While not quite up to last year’s five-win breakout season, Altuve is having another solid season for the Astros, hitting .300/.340/.409 with a 106 wRC+ this year. In his first three seasons in the majors, Altuve’s defensive numbers were not very good. Both DRS and UZR had Altuve as solidly below average while this year’s numbers have him above for a second baseman. With a small positional adjustment, Altuve has gained about half a win on defense in just one-third of a season. Like Stanton, Altuve is likely to be a very valuable player this season for the Astros, but that value should stem from his bat and baserunning as opposed to his considerably above-average fielding numbers.

Adeiny Hechavarria

Hechavarria’s defensive numbers over the past three seasons are not very good, but this year he is right near the top with Andrelton Simmons. Hechavarria has cut down on his throwing errors, but that alone is not enough to turn him into a great fielding shortstop, nor does it make him the third-best shortstop in the majors as his current 1.6 WAR suggests, placing him behind just Brandon Crawford and Jhonny Peralta. The other alternative, and it’s a possibility that Jeff Sullivan wrote about last year, is that Hechavarria is finally matching his talent to his defense.

Player defense does change over time, but right now we don’t have a lot of evidence to suggest that the numbers for players like Altuve and Stanton are anything but sample size blips in a reliable statistic given enough data. For convenience, I have put all the players used for the study below as well as the difference in the one-third of a season average over the three previous years and this year’s numbers.