The Royals’ defense has seemed worse because it is

Last night, the Kansas City Royals entered the ninth inning of a game against the Minnesota Twins, current occupiers of the second Wild Card slot that the Royals are pursuing, up 2-1. This was a situation in which the Golden Age Royals of 2013-2015 comfortably dominated, closing out close games with reckless abandon.

The Royals did not pull off the victory, mostly because closer Kelvin Herrera has turned into a teapot and forgotten how to pitch. Max Kepler cleanly singled to lead off the frame, and after that Herrera walked two and allowed two singles. That, combined with a sacrifice fly, turned into a trio of runs for the Twins. Herrera was bailed out of further damage by Brandon Maurer, of all people, which is like choosing the high school dropout as your SAT coach.

But one of those singles was a ‘single.’ In other words, it was really just a terrible defensive miscue. Alex Gordon and Alcides Escobar meekly ran together and just sort of watched it drop between them on what should have been an easy out. You can see it in Ed Zurga’s fantastic picture above, or you can watch it at 0:34 in this video.

It was the kind of blasé defensive miscue that has happened an awful lot recently. The Royals have played seven games in September and accrued six errors, and last night’s drop could have easily been ruled a seventh. Averaging one error per game is huge—no team since the 1994 baseball strike has averaged one per game over a full season, for reference—and, as we saw with last night’s play, errors can’t cover a full evaluation of a defense.

So has the Royals defense been worse this year? Yes, it has.

Not only has the Royals defense been worse this year, it’s been markedly worse than the other teams of the Good Royals era (the five seasons since 2012, the last year Kansas City had a losing record).

We’ll look at two different metrics: Ultimate Zone Rating (UZR) and Defensive Runs Saved (DRS). Both statistics essentially look at how often a given defender converts balls in play into outs relative to the league average, and after some calculations they present the data in terms of runs above or below that average. Since they do calculate things differently, there is sometimes discrepancy between the two; however, since they are presented in the same unit (runs above or below average) they are very easy to average.

Below is a list of the Royals’ seasons since 2012 by UZR, DRS, and their average:

Oof. This year is a huge outlier, as it’s the only DRS number below average and the only UZR number under +20; they average to be just below average. So why is this? Well, team defensive numbers are based off individual defensive numbers, after all, and individual defensive numbers do not like the 2017 Royals.

Of the 12 lowest DRS scores by any individual Royal season between 2013 and 2017, six of them are from 2017: this year’s campaigns by Melky Cabrera, Alcides Escobar, Jorge Bonifacio, Drew Butera, Mike Moustakas, and Eric Hosmer. The Royals are underrepresented at the top of the DRS leaderboard, too; under the same qualifications, but instead looking at the best seasons, only one 2017 season (Alex Gordon’s) exists in the top 16 of DRS numbers. It’s similarly bad with UZR; only one season from 2017 is in the top 22 (!) (again, Gordon), though UZR doesn’t quite hate as many players’ 2017 defense.

How did this happen? That’s actually rather simple. At the beginning of the season, the Royals swapped out Jarrod Dyson (one of the best defensive outfielders in baseball), replacing his playing time with a combination of Cabrera, Soler, and Bonifacio (the three stooges of poor right field defense). Never underestimate the impact of swapping a world-class defender for some very bad ones.

Furthermore, defense peaks early and starts its decline phase in a player’s late 20s, as per former Royals Review writer Jeff Zimmerman:

(Zimmerman has more stuff on aging curves here, and elsewhere too)

It just so happens that many Royals are in that defensive decline phase. Salvador Perez and Hosmer, the two youngest members of The Core that won it all in 2015, are in their age-27 season. Moustakas is in his age-28 season, and coming off major reconstructive surgery on his knee. Lorenzo Cain, Escobar, and Gordon are all north of 30.

Defense is tricky because it’s hard to evaluate and can fly under the radar, but in this case your eyes are telling you the truth: the Royals haven’t seemed as good defensively because they aren’t. They still have some superbly talented defenders, but Father Time remains undefeated.