One of the story lines from last year's Astros' campaign was the defense, which was very bad. This was particularly unnerving for a team which had perhaps the best defense in the NL in 2005. Adam Everett's injury undoubtedly play a role in the defensive fall off in 2007. But the problem positions were all over the field.
Ed Wade and Cecil Cooper both said that defensive improvement would be a priority this year. However, going into the 2008 season, the net impact of the player additions/subtractions on defense was an unknown. Some positions seemed to be in for improvement (CF), some seemed likely to continue to decline (LF), and the impact of losing Everett at shortstop seemed like a bad thing for the overall defense. So, let's look at how the defense has fared so far in 2008, one month into the season.
Several news articles have pointed to the Astros' outstanding fielding percentage. The Chronicle's fan blogger, Chip Bailey, recently noted that the Astros are best in the league in avoiding errors, suggesting that the team is on a pace to set team defensive records. Link Although that is good news, fielding percent and errors are not the best statistic for evaluating defense. Players with poor range sometimes can avoid errors simply because they don't get to the ball. Range-based defensive metrics help tell the story. Several range based defensive measures are frequently cited, and they can sometimes produce differing results. For this article, I will rely upon the current Revised Zone Rating (RZR) at Hardball Times.
The usual cautionary note is that the sample size is small for defensive metrics. After one month of play, treat the evaluation with a grain of salt. Also, I normally evaluate both RZR and Out of Zone (OOZ) plays, when using the HT stats. However, at this early stage of the season, the differences in OOZ plays doesn't appear to be something which will affect the results significantly.
According to the RZR results so far, the Astros' defense isn't the best in the NL, but it has been very good. All kinds of team stats are here. The Astros team RZR is .859, good for third in the NL; only St. Louis and San Diego have better RZR scores. The Astros' infield defense is 4th best in the NL, based on RZR (.811), behind the Cubs, Cards, and Pads. The Astros' outfield defense is also 4th best, (.929 RZR), behind the Cards, D-Backs, and Mets. (Maybe we see why the Cardinals' pitching has been so good this season.)
Given that the Astros' team rankings appear to be improved, individual player RZR rankings should be interesting. Because Matsui and Wigginton have been out of the lineup with injuries for long periods, the sample size is too small to include them yet. The RZR results and NL ranking among qualified players at the positions:
Berkman, 1b. .971, ranked 1st.
Tejada, SS, .886, ranked 3d.
Lee, LF, .833, ranked 7th.
Bourn, CF, .957, ranked 2d.
Pence, RF, .943, ranked 3d.
Blum has played the most at 3d base, and if he had qualified, he would have been 5th among 15 qualified NL 3d baseman. Loretta has played the most 2d base, and if he had qualified, he would have been 9th out of 12 NL second basemen.
My first reaction is that Wade's plan to improve the outfield defense by placing Bourn in CF and Pence in RF seems to be working. Both have displayed outstanding range. For those of us who have watched him play, Bourn has been every bit as good as advertised on defense. Bourn is barely nudged out of 1st place in CF by Rick Ankiel and ranks in front of Arizona's Chris Young. Bourn also has a large number of out of zone plays, considering his lesser playing time (due to the recent injury). My second reaction is that Berkman is doing a surprisingly good job at 1st base. His RZR ranks higher than Pujols, who normally is the gold standard for defense at the position. This is surprising because Berkman's RZR score in 2007 was not very good, and many consider him a weakness on defense. However, in my view, Berkman has the physical skills to become a very good fielder...if he cuts down on the mistakes. And apparently he has, so far.
Finally, the switch from Tejada to Everett at shortstop hasn't hurt as much as I expected. Since Everett is currently sitting out with an injury in Minnesota, it's hard to fault Wade's decision here. Tejada is among the league leaders at shortstop, behind Tulowitzki and Izturis, both of whom are gold glove quality. Tejada's arm strength is outstanding, and allows him to get outs even if he isn't in great position to make the play. Based on what little I've seen of them together, Kaz Matsui and Tejada working together on the double play will be fun to watch. In interviews, Tejada says that he came to spring training with a determination to improve his defense with extra work on the back fields during the spring. I don't know if that is the reason for the improvement, but I hope Tejada maintains his current defensive pace.
The same can be said for the rest of the defense. In the future, the switch from Blum to Wigginton may bring a defensive decline at 3b. However, as Matsui takes over from Loretta at 2d, a defensive improvement is likely to be seen at that position.