Goatriders of the Apocalypse

The Chicago Cubs and Defense: A Three-Year Retrospective

The guys at Fangraphs have done it again. Visitors to their site can now look at aggregate statistical data. If you ever wondered who led the Cubs in WAR (as calculated by Fangraphs) between 2005 and 2010, it's never been easier to have your question answered.

Personally, I love stats. Always have, always will. It probably has something to do with the fact that I'm a complete math nerd (love me some xkcd.com, e.g.). And it's a big part of why I love baseball: as far as sports-related statistical analysis goes, baseball's the best there is. Kudos to you, Bill James et al.

But having been involved in the sabermetric conversation for some years now, I've come to find that stats have their shortcomings. At the very least, those who deride the value of statistics have an argument worth making. At the macro level, their argument is this: stats don't tell the whole story. Great numbers are great, but it sure seems like "some guys just win."

Perhaps the one aspect of baseball to which this adage can be most accurately applied is defense. Fielding ability -- and by extension, the proper way to measure it accurately -- is the most hotly-contested numerically-related issue in baseball. Everyone's got their own method, and different systems churn out different results for different types of players.

With Fangraphs' release of aggregate data, I've decided to take a look at some defensive statistics for Chicago Cubs players over the past three seasons. I hope the numbers I've pulled out from various spreadsheets serve as a guide to an ongoing discussion about the team's abilities and shortcomings. (Note: Fangraphs does not evaluate defense for pitchers or catchers.)

Marlon Byrd had a great year with the bat for
the Cubs in 2010. But his center field defense might make him the
team's most valuable player over the course of Lou Piniella's tenure.

Based solely on their performance in center, Reed Johnson, Jim Edmonds, and Kosuke Fukudome have been three of the Cubs' worst overall defenders
relative to other major leaguers at the position since 2008. In
contrast, Fangraphs estimates Marlon Byrd saved about nine runs more
than the average center fielder in 2010, boosting the team's overall
record by a full win.

This might be the most telling of all Chicago Cubs
defensive factoids: since 2008, the team's best defender has been
Alfonso Soriano. The man is certainly error prone, but his decent speed
and strong arm give him a plus-rating as an overall defender.

now that teams know not to run on him, Soriano's cannon is less valuable in terms of generating outs. But there's certainly something to
be said for holding runners.

Everyone knows Starlin Castro struggled with errors
last season, but on a per-inning basis, his range is eight times better
than Theriot's in terms of runs saved. That sounds about right.

Over the last three years, Aramis Ramirez has a below-average defender at third base in every facet of the game measured by Fangraphs: double play ability, range, and errors made.

The weakest part of Aramis' defense over the past three seasons was his range in 2010. After being an asset on defense in 2007, Ramirez' range has been suffering from an annual decline. Even if he bounces back with the bat in 2011, this could be Aramis' last year at third for the Cubs.

Derrek Lee's range at first base puts him among the
league's best defenders at the position. Based on three years of data,
only three other major league first basemen have better range: Ike Davis
(NYM), Daric Barton (OAK), and Joey Votto (CIN). 

Having said
that, defense at first base might be an overrated skill. The difference between the league's absolute best and worst defenders among qualified
first basemen appears to cost a team no more than one win over the
course of a season.

Over the past three years, Lee has been about
five defensive runs better than Carlos Pena per 150 games played.
Statistically, that total represents just half a win on a team's
expected record.

The numbers say the Cubs' best defender at second
base since 2008 has been Jeff Baker, but that probably has more to do
with the fact that he hasn't spent much time there. Both he and Mike
Fontenot rate favorably at the position.

What's more telling
about Baker and Fontenot's numbers is that they're better than those of
either Blake DeWitt or Ryan Theriot. Cub fans clamored constantly for
Lou to move Ryan over to second, but in 545 defensive innings played at
the position Theriot's range was below-average compared to the rest of
the league.

The Cubs may have a long-term solution for second base in mind, but don't bother asking me what it is because I have no idea.

I've saved the most boring for last: Kosuke Fukudome and Tyler Colvin are both able defenders in right. Both players will give Mike Quade an above-average option defensively for a late game double-switch.

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