Incited by this comment by Keith Law:
Thoughts on Jon Jay?
Klaw (2:19 PM)
If he’s really a .350 BABIP guy, then solid everyday player. I’ll admit I never saw that coming, but he’s at .347 through almost 1000 major league PA. He just doesn’t do anything else well – isn’t patient, doesn’t have power, not a good defender in CF – but consistently high batting averages cover a lot of sins.
...and perhaps an undervaluing of Jay's defense by baseball fans, I decided to look at UZR and Jay's career in the major leagues. Now, UZR is a very volatile defensive stat, but I'm going to use it anyway, since Jay has been playing in the major leagues for a while now, and Jon has logged 1087 innings in center.
Since 2010, 36 center fielders have had at least 1,000 innings in center field. The worst defensively of those guys is Matt Kemp... but he flat out rakes. Still, it would probably be a smart move to move him to a corner spot for the Dodgers. Surprisingly, Andrew McCutchen is another player that might not want to be playing center field for too much longer.
Another surprise for me is that Colby Rasmus has a career -14.3 UZR, making him about as good defensively as Curtis Granderson. While UZR is an objective means to evaluate defense, I still take it with a grain of salt even in over 1,000 innings. For what it's worth though, Colby has had over 2,900 innings in center now, and his UZR/150 is -7.5. The better negative UZR center fielders are: Angel Pagan, Alex Rios, Drew Stubbs, and Jordan Schafer.
So, to address Keith Law, who looks like an average center fielder? To me, "not good defender in CF" is a very subjective statement, but I will take it as anyone average or less is not "good" at defense (sure it could mean that good defense is also average defense, but for the purposes of this article, I'll assume he means that average is not good).
Average defenders with over 1,000 innings in center field since 2010 are BJ Upton at 1.1 UZR/.7 UZR150, Cameron Maybin at 1.7/1.3, & Coco Crisp at 2.5/1.1. Since this is pretty arbitrary, I will say that the worst of the "good" center fielders is Michael Saunders at 3.2/4.0.
Which brings us to the good or just a tick above average defensive center fielders: Jon Jay. I know this seems like I am trying to make a point, which I am... but Jay has been worth 4.6 UZR and 5.7 UZR/150. 16 center fielders have been worth more as defenders since 2010 by UZR, and 19 have been worse. Looking at UZR/150, which is a normalized version of UZR, only 14 center fielders have been better and 21 worse. Does this make Jay a "good" defensive center fielder? To me, yes, but that is up to you to decide.
What we can say pretty surely is that ten center fielders are elite, or "really good" at defense since 2010. From best to worst of this top ten: Tony Gwynn*, Peter Bourjos, Jacoby Ellsbury, Franklin Gutierrez, Andres Torres, Carlos Gomez, Chris Young, Michael Bourn, Denard Span, and Austin Jackson. *Gwynn has by far the least amount of innings played compared to the rest of the top ten defenders in center, so perhaps he is not "the best".
So, I think it is safe to say that Jon Jay is not an objectively bad center fielder. He is at least average, and arguably good at defense. Personally, to my "scout" eye, I'd say Jay is at least good at defense, and he is not slow of foot. As for the very traditional way of looking at things, he has only made 3 errors in center, so I think it is safe to say he is very comfortable out there, and looks like it to me (except when running into walls). Another runner into walls, Rick Ankiel, is also objectively not bad at defense with a 4.4 UZR/150.
As for Keith Law's assessment that Jay has no power, well, I wouldn't go that far Keith. While in recent years center field has become a position with the potential for some power with the likes of Matt Kemp and Josh Hamilton playing out there, it is mostly known as a position that is not as power-centric as the corner outfield spots.
This assessment that Jay has no power is only true if you say that Alex Rios, BJ Upton and Austin Jackson have no power. While I could see why one would think that that means someone has no power, I could also argue that Jay's .420 SLG% in center field is only bettered by 14 center fielders since 2010, and that Jay slugs better than 15 center fielders since 2010. To me, that seems squarely in the average power range for center fielders.
Keith, you might want to re-evaluate your conclusions here.
And his (yes, BABIP boosted) career wRC+ of 115 in center field is the same as former All-Star Shane Victorino. Jay trails only elite center field hitters like Josh Hamilton, Matt Kemp, Andrew McCutchen, and Curtis Granderson in that stat. So he is the best of the non-elite center fielders in offense. The idea that Jay just doesn't do anything else well except for batting average just doesn't fly.