Has the Red Sox defense really improved?

The signing of Adrian Beltre (testicle jokes aside) has fans buzzing about the Red Sox defense and its ability (or inability) make up for the team’s obvious hitting woes. What I’m wondering is how sure are we that it will be good enough to make up for the lack of fire power? After some research, I believe the Sox are improved but not as much as you may think.

I’m no Sabermetrician but I do subscribe to the theory that defense should be quantified by more than fielding percentage. I love being able to watch a game and evaluate what’s going on without using solely statistics as a barometer.

Metrics such as Probabilistic Model of Range (PMR) don’t really do it for me because I don’t think it’s realistic to try to measure the difficulty of every play a fielder tries to make. There are just too many variables in play. While Mitchel Lichtman’s Ultimate Zone Rating (UZR) from FanGraphs isn’t perfect, it’s probably the best tool for those of us caught between perceptions of how to rate defense.

The old-school thought process revolved around watching baseball and determining whether the play could have made a play on the ball, i.e. Bill James’ Range Factor. Statistics have evolved to the point where we know if the Giants’ right fielder was running toward a down-wind fart in the 8th inning of their July 18 game against the Padres. OK- maybe I’m exaggerating. Maybe I just wanted to make a fart joke.

If you want to browse through the explanation of UZR and the different contexts involved, take a look here. UZR provides some middle ground in that it offers us relevant statistics into whether the fielder was responsible for the ball hit toward them. The difference between this and something like PMR is that either the ball was in their “zone” or it wasn’t (albeit there are some flaws, such as not counting assists). PMR leaves too much subjectivity and too many variables.

These are obviously not new concepts (UZR came out in 2003) but I’ve just found it to be interesting to see how they pertain to the Sox, and specifically whether the new guys offer a substantial upgrade over Jason Bay, Mike Lowell and Alex Gonzalez.

I do like how UZR takes ballpark and pitchers’ tendencies into account but, here comes the old-school in me, I watched Jacoby Ellsbury play every day in 2009 and he is a good center fielder. Obviously, he’s not Willie Mays but I don’t agree his UZR rating of -18.6, which is the worst among center fielders in baseball. Sure, there were a few times where he took circuitous routes to the ball but I don’t feel as though there are many who can play much better in Fenway’s cavernous center field.

For the purposes of this discussion let’s take a look at the 2009 Red Sox vs. the newcomers’ UZR ratings.

The 2009 Red Sox by defensive position:

CF- Ellsbury -18.6 (last among CFs)
2B- Pedroia 9.8 (third)
*1B- Youkilis 5.7 (first)
C- Martinez N/A- There are no UZR ratings for catchers.
LF- Bay -13.0 (second-worst)
RF- Drew 10.5 (second)
3B- Lowell -11.1 (This would have been the worst had he qualified. Down from 10.4 in ’08. Yikes.)
SS- Gonzalez 6.7 (eighth)

*This was in 78 games at first. His UZR at third was -1.6. This could have been more concerning without the Beltre signing.

New to Fenway:
SS- Scutaro 0.9 (13th)
CF- Mike Cameron 10.0 (third)
3B- Beltre 14.3 (fourth)

At a glance, UZR indicates that Cameron (moving Ellsbury to LF) and Beltre are improvements over their predecessors and Scutaro is a downgrade from Gonzalez.

Once you take in all these statistics as well as the point that someone like Ellsbury is far better than his rating indicates, the Sox defense as a unit may not be that much different than last year. There are still four of the seven listed returning to a Sox defense that finished 16th in team UZR last year. Are Cameron, Beltre and Scutaro going to make enough of an impact to improve the defense to the point that it doesn’t matter the Sox can’t hit with RISP? I really don’t think so.

There is a clear upgrade in Beltre over Lowell. There’s no debating that point. Mike Cameron replacing Ellsbury is an improvement but I don’t believe he will field markedly better in Fenway Park. Ellsbury moving to left shouldn’t matter too much in the grand scheme of things because we all know left field in Fenway is a joke. Throw in the huge loss of Gonzalez’s defensive wizardry at short and this team has really only improved in one area total.

Take these stats with a grain of salt, obviously, but don’t completely buy into the fact that this team has gained the identity of defense-first.