Exciting news this weekend, FanGraphs is now providing UZR data — Ultimate Zone Rating — on it’s website. UZR for those who don’t know, is one of the more heralded defensive systems out there. Consider UZR another handy tool to stick in your tool belt when it comes to player analysis. UZR splits the field into “zones” — hence the ‘Z’ in UZR — and calculates how many outs each player was expected to make compared to average. UZR looks at the probability of turning a ball in play into an out — how hard it was hit, where it was hit, what kind of hit (line drive, groundball, flyball) it was — and then makes a few adjustments. Adjustments such as: park factors, batter handedness, GO/AO ratio of the pitcher pitching, and base/out situation.
The Hardball Times has a nice article on UZR and some other defensive metrics here. You can also read some of MGL’s original posts on UZR which prove to be very informative if you are curious about the inner workings of the system. The bottom line is that UZR is one of the more respected defensive systems out there and to be able to get it for free, is awesome news. Let’s check out some 2008 UZR numbers for the San Francisco Giants.
2008 Giants Fielders by UZR (min. 300 innings)
| Name | Pos | Inn | UZR | UZR/150 |
| Randy Winn | RF | 1108.1 | 16.9 | 18.9 |
| Omar Vizquel | SS | 657.2 | 5.3 | 13.8 |
| Fred Lewis | LF | 905.2 | 7 | 12.1 |
| Rich Aurilia | 1B | 477 | -0.2 | -0.5 |
| Jose Castillo | 3B | 820 | -0.9 | -1.6 |
| Eugenio Velez | 2B | 449.2 | -0.9 | -3.2 |
| Ray Durham | 2B | 535.1 | -1.3 | -4.1 |
| Rich Aurilia | 3B | 427.2 | -1.2 | -4.9 |
| John Bowker | 1B | 550.1 | -1.9 | -5.9 |
| Aaron Rowand | CF | 1275.1 | -12 | -11.1 |
| Emmanuel Burriss | SS | 315 | -3.2 | -14.1 |
The table is sorted by UZR/150 or how many runs a player would save over 150 games. I’ve also limited my data to fielders with a minimum of 300 innings played at a defensive position.
A quick note on sample sizes and defensive metrics. Looking at Burriss’ -14.1 runs below average for position might freak you out but understand that 315 innings is but a tiny drop in the bucket. It doesn’t tell us anything about Burriss. It has no predictive value and all we can say is that in 315 innings played at shortstop in 2008, he was below average. Is that his true talent level? We don’t know. The sample size is just too small and ideally you’ll want a few seasons worth of data before you try and figure out the true talent level of a player. Dave Cameron makes a good point on USSM about comparing players across positions. Burriss may have been below average in his brief 315 innings but UZR will compare him to his peers; ie: other shortstops. This is good because we want to know how Burriss stacks up against other shortstops but also remember that shortstops, as a group, are some of the most athletic defenders on the baseball diamond. A -10 shortstop isn’t the same as a -10 left fielder or first baseman, who are on average, less athletic. Burriss is being compared to Omar Vizquel, Cezar Izturis, J.J. Hardy, and Jimmy Rollins. Fred Lewis is being compared to Adam Dunn, Carlos Lee, and Pat Burrell. Context is important when thinking about these rankings.
Is Randy Winn one of the most undervalued players in baseball? Every year he hits about the same, providing league average offense — wOBA+’s of 96, 107, and 108 over the last three seasons — while playing some of the best right field in all of baseball. Last season, Winn was the best defensive right fielder in the game by UZR. He was worth +18.9 runs by his defensive play alone, that’s nearly +2 wins. This isn’t anything new for Winn. From 2006-2007 he was worth +15.3 and +11.9 runs above average in right field. Winn’s game is extremely un-flashy but as an overall player, he’s been one of the better Giants over the last couple of years.
Besides Randy Winn, Omar Vizquel and Fred Lewis are the only other players who scored as above average fielders in UZR. Vizquel’s bat might be dead but his defense is still very good. If Vizquel would have somehow played 150 games — that’s not going to happen any more — he would have saved 13.8 runs. A team who needs a late inning defensive replacement might consider Vizquel, just don’t let him hit too much. Fred Lewis did well in LF in ’08, he was worth +7 runs above average for his playing time and would have been closer to +12 runs in 150 games played. Lewis’ good foot-speed helped him to overcome sometimes awkward routes in LF to be a above average defender.
The Giants have to be worried about Aaron Rowand’s defensive performance in 2008. Rowand has been a good defender in CF but he saw a complete reversal of fortune last year. Check out his UZR’s from 2002-2007: +12.6, +9.2, +9.6, +16.5, +4.6, and +7.9. Those are solid defensive numbers to be getting from your CF. I’m not sure Rowand is the type to age well — plays hurt all the time, runs into walls, GAMER, etc. — and the Giants have to be hoping he’s not hitting a wall (no pun intended) at 30-years-old. If the team does have to move him out of center, I think he’ll be headed to LF. Playing right field in AT&T is almost like playing a second center field and if Rowand can’t hack it in CF, I can’t see him doing much better in RF. Next year will be a big year for Rowand and if he continues to slide, his contract starts to look much worse. I’m hoping he was hurt but we can’t just throw out all of his 2008 data and wish that it didn’t happen. For what it’s worth, CHONE’s defensive projections for 2009 see Rowand bouncing back to a +7 CF.
The rest of the list has the usual suspects. Rich Aurilia is an average defender at first base but takes a dip at third. John Bowker struggled at first base in ’08 and I’m guessing the Giants won’t revisit that expirmanet anytime soon. Velez rated better than I thought he would have, but remember, the sample size is too small to draw any conclusions from. Jose Castillo played better at third than I expected and Durham is closer to an average defender than I expected. Ray might have a couple of years left in the tank if he wishes to pursue them. New guy Edgar Renteria isn’t on my list, but he scored as a +1.1 shortstop for the Tigers in 2008. PMR hated Renteria and plus/minus had him as below average, but he might not be as bad as we thought. If you check out his fielding data over the past four years, you can see he looks to be pretty steady, fielding around average each year.
