templeUsox wrote:

---

Because it's unreliable.

Care to elaborate?

Cem21 wrote:

---

Ellsbury is a plus defender in CF. Defensive metrics are fine as a point of reference or as a conversation piece, but anything past that is pushing it, especially when it comes to outfield defense. If you are going to say that Ellsbury has a weak arm and can't throw anyone out, I would agree with that 100%. But, some of the other things floated out there like he doesn't have great range or gets bad jumps on balls are simply not true.

Ellsbury can cover tremendous ground in the outfield and with the exception of the occasional ball hit right at him, he judges balls well off the bat. He goes back on balls hit into the gaps extremely well and hunts balls down. If it weren't for 365 foot flyballs hitting off the Wall, he'd eat up even more balls out in CF. It is true that his elite speed enables him to get to balls that otherwise he shouldn't, but that is a quality you want out of your centerfielder to begin with and that should only bolster his defensive value, not punish it through misconceptions.. Is there room for improvement for Ellsbury in taking the next step towards being one of the elite CF in the game? Yes. But, this notion that he is a subpar CF or that his play in CF is subpar is the result of some metrics thrown together to attempt to quantify an aspect of the game that by all admittance is the most difficult to quantify through metrics or numbers.

When defensive metrics point to a conclusion that is different from conventional knowledge one should look at why it is that this metric points to a different conclusion. This is made somewhat harder by not having the play by play data that is used to compile UZR.

From my watching of the games I saw that Ellsbury did indeed make great plays when moving laterally. Yet when going back and forth the results seemed to be weaker. For whatever reason, a lot of balls seemed to fall in front of Ellsbury. I still don't understand why Ellsbury wasn't in postion to catch a the looping fly ball from Vladamir Gurerrero that basically ended the Red Sox season.

I also don't think that this is just a case of defensive metrics punnishing Ellsbury for not catching an inordinate amount of uncatchable balls. According to Baseball Prospectus's ESPN "Kiss em Goodbye":

Jacoby Ellsbury is fast and makes some impressive-looking plays, but he takes awful routes and plays deep because he doesn't go back on the ball well with Vladimir Guerrero's game-winning hit on Sunday a prime example.

Additionally in listening to talk radio the last few days, I defintely heard a comment from a beat writer (Maybe Tony Mazz?), indicating that the Red Sox had "considered moving Ellsbury to LF in the past". I wouldn't be certain that the Red Sox completely buy into your comments above.

Finally, I am skeptical that the Red Sox would sign a CF with a long term repuation for defensive to a long term deal if they really thought they had a CF on the verge of becomming elite defensively.

All and all there seems to be some smoke here. It could very well be that an unusual amount of uncatchable balls at Fenway influenced his poor defensive ratings. But I don't think that taking those away would turn Ellsburry from the lowest ranked CF in the majors to one of the best.