For anyone that cares and hasn't seen, over at Fangraphs, they have the first UZR updates of the year. In addition to that, the formula for UZR has been modified to compensate better for "quirky parks and portions of parks," like left and center in our beloved Fenway.
So while these changes didn't make a difference for a lot of players, Bay and Ellsbury were both pretty heavily affected. With the new formula, Bay actually posted a positive UZR of 1.9 last year (and yes, it is only one of only two years he has had a positive UZR), while Ellsbury's isn't quite so far down in the basement- up to -9.8 in 2009 (which is his only negative year).
No, we all know UZR is not the be all end all of everything and one year is too small of a sample size, but some fun information to chew on.
And if you want to look at obnoxiously small sample sizes, check out this years UZR numbers so far! For what it's worth (absolutely nothing), Bill Hall, Marco Scutaro, and Kevin Youkilis are the Red Sox with negative UZR so far this year.
Also, for what it's worth (very little), when I was looking for a picture for this post, I could not find a picture of Bay actually making a catch in the field, just misplaying balls or failing to make a catch. So take that how you want it.