Impact of Royals’ Defense on the Pitching Staff


Coming into the season, there was a lot of talk about the Royals having one of the best defenses in the league. That reputation has been tested so far in 2013. Currently, the Royals are tied with the White Sox for last in the American League in fielding percentage (.982). They also have committed the second most errors in the league with 37. Judging by those very basic defensive statistics, this defense is a bad one. However, we know that looking solely at errors committed doesn’t tell the whole story, since the determination of what is an error and what is a hit can vary from scorekeeper to scorekeeper, and from situation to situation. When we look at some more advanced metrics, the Royals are rated much more highly.

Mandatory Credit: Kevin Jairaj-USA TODAY Sports

As of right now, the Royals lead all of Major League Baseball with a UZR of 21. The second best team in that category, the Diamondbacks, have a UZR of 15.9.

I know. I was surprised, too.

Digging deeper, we can see the impact the defense has had on the pitching staff. The Royals’ staff currently sports an ERA of 3.77, which is good enough for 5th best in the AL. But their FIP is only the 11th best in the AL at 4.22. This suggests that the pitching staff is getting better results than one should expect, at least in part due to the defense behind them. Focusing on just the rotation shows a similar pattern. Their 4.37 FIP is the 11th best number in the league, while their 3.98 ERA is the 6th best in the league. It’s the same story with the bullpen, too: 3.85 FIP (10th), 3.22 ERA (3rd). So overall, the defense seems to have helped the pitching staff.

But let’s take a look at the pitchers individually to see if the same trend holds for all of them. I should preface this by pointing out that for pitchers, it is still somewhat early in the season, so the usual small sample size caveat still applies. (These numbers were pulled prior to Tuesday’s game against the Twins.)

NameERAFIPBruce Chen



Greg Holland



James Shields



Ervin Santana



Luke Hochevar



Tim Collins



Jeremy Guthrie



J.C. Gutierrez



Aaron Crow



Luis Mendoza



Kelvin Herrera



Wade Davis



Of everyone who has pitched at least 5 innings this season, Chen, Shields, Santana, Hochevar, Guthrie, Crow, and Herrera all have lower ERAs than FIPs. Only Holland, Collins, Gutierrez, Mendoza, and Davis have lower FIPs, suggesting the former group is receiving a bit more help from their defense than the latter group. Collins, Holland, and Davis in particular should be expecting better future results. Those three all have ERAs at least a run higher than their FIPs, so I wouldn’t be terribly surprised if their actual results begin to improve. I probably have a bit more faith in Collins and Holland in that respect, since Davis kind of resembles another pitcher we saw come to Kansas City and look inconsistent with solid stuff, on his way to putting up strong FIPs with poor actual results. Stats don’t always tell the whole story, of course, and it seems to me that Davis leaves the ball up in the zone too often, which is not a great strategy for success. Throwing too many hittable pitches also can result in an extremely high LD% (Davis sports the 2nd highest number in baseball among qualified pitchers), which makes the defense’s job much more difficult. He is striking out 7.89 batters per 9 innings, so if he can make some adjustments to keep the ball down more, I’d feel much more comfortable about Davis seeing significant improvement.

Mandatory Credit: Kevin Jairaj-USA TODAY Sports

On the other end of the spectrum, Chen, Santana, Guthrie, and Herrera have ERAs that are at least a run lower than their FIPs, meaning a bit of regression could be expected, although Herrera’s struggles with the home run ball will likely normalize, and I actually think his numbers will improve, despite what his FIP suggests. I also don’t think Santana will fall off too much as long as he maintains his strikeout and walk rates, because his HR/FB rate is well above his career average, so that could cushion any letdown he receives from the defense, as you can see from his 3.52 xFIP. As for Guthrie, he’ll need to start striking out more batters if he hopes to maintain his current productivity level. I think it’s possible, but he’s relying on the defense far too much right now, and even if his HR rate normalizes and gets closer to his career average, the actual results could still turn out to be poor, as evidenced by his 4.63 xFIP.

Basically, the pitching staff isn’t doing a great job of controlling the things they are able to control. They’re in the middle of the pack in K/9, a little above that in BB/9, and the HR/9 allowed puts them near the worst in the league. But when the pitchers are allowing balls in play, the defense is doing their part by converting them into outs and helping the rotation and bullpen get results.

And as we’ve seen over the past month with the way this offense is going, the pitchers can use all the help they can get.