The Importance of Defense in a Fantasy Baseball Context

If I preach about anything on this blog one of them is putting things into the proper context. David Golebiewski at Fangraph.com has posted a terrific series of articles that examine how the defense of the Texas Rangers and the improvement of Edwin Jackson, and also the new and improving defense of the Seattle Mariners fit into fantasy baseball context. This is great stuff that you should read.

Rangeless Rangers Compound Pitching Problems

So, the vast majority of Texas’ starters were crappy, regardless of dimensions of their home ballpark. That’s not breaking news. However, the Rangers’ fielders did those starters no favors in 2008. While Texas featured some heavy hitters, several prominent players were lethargic with the leather.

David Appelman recently added yet another great feature to this site: Ultimate Zone Rating. Using a fielding model developed by Mitchel Lichtman, UZR allows us to calculate how many runs above or below average a fielder is per 150 games played (for further details and discussion, look here). Perusing the Texas team page, it becomes apparent that while the Rangers’ offense is strong up the middle, some of those runs are punted back on defense (and, in Young’s case, on offense as well):

CF Hamilton: -12.6 UZR/150
2B Kinsler: -4.4 UZR/150
SS Young: -3.7 UZR/150

This is especially significant with all of the young and extremely talented pitching about to come out of the texas Rangers minor league system. It also helps to explain why so many pitchers fail in Texas only to make dramatic improvements elsewhere. The Park Factors and Bad Defense combine tocreate a worst-case scenario for pitchers in Texas.

Trade Fallout: Jackson Jumps to Motown
In 2007, Jackson posted a 4.90 FIP. In 2008, despite the huge difference in ERA, that FIP figure remained static (4.88 FIP). While he knocked off over a walk per nine innings from his line (from 4.92 BB/9 in ‘07 to 3.78 BB/9 in ‘08), his strikeout rate dipped considerably, down from 7.16 per nine in 2007 to just 5.3 in 2008.

It wasn’t really Jackson that improved, but rather the defense around him. The dramatic shift in the quality of Tampa’s D has been well chronicled. After posting a gruesome -54.2 UZR in 2007, the Rays skyrocketed to +70.6 in ‘08 (for those of you scoring at home, that’s about a twelve-and-a-half win swing). Jackson’s BABIP was .351 in 2007, but with the best defensive squad in the majors flanking him in 2008, that number dropped to .301. He also benefitted from stranding 76.1% of runners on base, well above his 69.7% career average.

This makes the Tigers acquisition of Jackson even more interesting. The Tigers have improved their defense this offseason but is it enough to allow Jackson to stay at the level he reached last year? If it is and Jackson can increase his strikeout rate and maintain or even improve his BB/9 from last season we could be looking at a real breakout.

Meet the Mariners’ New Outfield D
As a whole, the M’s outfield was -25.5 runs below average by UZR and -15.2 runs by the Plus/Minus system (the big difference in RF is due to Dewan’s system liking Ichiro’s work there and UZR rating it as slightly below average).

Now, take a gander at the new-look Seattle D. For the sake of making this comparison easier, let’s assume that:
1. Chavez, Gutierrez and Suzuki all make 150 starts and play 1350 innings apiece.
2. The fielding metrics compiled by Gutierrez are docked 15% (it’s far from perfect, but it’s an attempt to account for the added difficulty of playing center), and Chavez and Suzuki play to the levels that they have shown in the corner spots during their respective careers. For Chavez, I added his equally stellar work in RF to his projection to make the sample size larger (the majority of his career has been spent in center).

LF Chavez: 20.3 UZR/150
CF Gutierrez: 18.3 UZR/150
RF Suzuki: 7.3 UZR/150

If this trio plays 150 games, they project to be nearly 46 runs above average with the leather. Compare that with the embarrassing work done by last year’s Ibanez-fueled, molasses-covered group: if the M’s get league-average defense from their extra outfielders (filling out the additional 12 game gap), that’s a swing of over 70 runs in outfield defense, or seven wins (!)

An improved defense as well as an improved offense means good things are in store for the Seattle Mariners pitching staff. I'm especially intrigued with the improvement that is possible for Felix Hernandez.
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