The 2010 Seattle Mariners have, to put it mildly, not quite lived up to pre-season expectations. A full post-mortem can wait until after the season, along with the attendant I-told-you-sos and other fun. Rather than focusing on what went wrong with the Mariners and why some people were wrong about them (including me — I didn’t think they’d win the division, but I thought they’d be around .500), I’d simply like to focus on a sentiment I encountered recently: that the utter collapse of the 2010 Mariners proves that the recent emphasis on defense (as exemplified by the Mariners’ personnel decisions) shows that fielding to be “overvalued.”
There are a number of related complex issues: the objectivity of recent defensive metrics, the difficulty of projecting defensive performance based on those metrics, integrating that data with scouting information, and so on. These are all important and should not be ignored (See here and here for some good recent work). For now, I want to deal with polemically the most basic claim: that the 2010 Mariners in themselves somehow show that pursuing players based on their apparent value in the field is a “flawed” strategy. We aren’t discussing whether or not current defensive metrics are good or not (after all, one could pick good defensive players based on scouting reports), or whether the Mariners picked the right players. Those are important, but I’m starting with the more simple issue of whether “defense is overrated.” Perhaps this is a straw man, but I think it’s one that at least needs to be cleared out of the way before more serious discussions can get underway.
The most obvious answer, of course, is that a run saved is still as valuable a run earned (generally speaking). Unless the Mariners or any other team emphasizing defense is likely to score zero runs a game (and if the 2010 Mariners didn’t accomplish that, I’m not sure who could, but more on that later), run prevention in general is a perfectly sound strategy. Moreover, one team failing to win through this strategy hardly “proves” anything. If it did, well, the San Diego Padres are winning the NL West against almost everybody’s expectations, and, what do you know, they currently lead the league in fielding runs saved according to UZR. So there.
While the Mariners’ fielders haven’t performed as well as expected, that they’ve been good (about 14 runs above average according to UZR) while the team has failed to win is the sort of thing that one might point to when saying that “defense is overrated.” Except, of course, that people have forgotten the one thing that everyone knew would be a problem for the 2010 Mariners: scoring runs. Again, this is not a full evaluation of what the Mariners could or should have done differently in putting the team together, but rather a look at what is happening right now. And right now, the Mariners have the worst team wOBA in the major leagues at .289 (league average is around .325).
To match some faces to this offensive futility, here are the current wOBAs of the 10 Mariners with the most 2010 plate appearances so far. In parentheses, I’ve included each player’s preseason Marcel projection, since that is the simplest projection system and gives a sample of what one might have reasonably expected from each hitter based on recent seasons:
Ichiro Suzuki .330 (.346)
Chone Figgins .293 (.344)
Jose Lopez .265 (.321)
Franklin Gutierrez .313 (.332)
Milton Bradley .289 (.372)
Casey Kotchman .289 (.334)
Josh Wilson .298 (.293)
Michael Saunders .331 (.313)
Jack Wilson .265 (.305)
Whoever you want to blame (or not blame), that is simply stunning. But I’m dancing around the issue: the point was not whether the Mariners should have seen this coming (on offense or defense), but rather whether this team’s actual performance shows that defense has been overvalued. Even if one thinks that a single season by a single team “proves” anything, I don’t think you can go much further than this: it doesn’t matter how good a team is on defense if they hit worse than Jason Kendall (.290 wOBA as of today).