July 13, 2001
Derek Jeter's DDebates about defense in baseball can be extremely contentious and frustrating. There's very little in the way of a generally accepted canon of evidence upon which people will agree, and a great deal of weight is place on personal observation. That makes it very difficult to question someone's position about a particular player without at least implicitly impugning their observation ability. I've seen grown, mature men nearly come to blows over the defensive prowess of Corey Koskie. Arguments over defense can even ruin a romantic cruise.
Last year, I did a partial series on who I thought were the best and worst defenders at each position. Typically, I get perhaps 50 to 100 e-mails for each column I write, and that number has increased a bit as we've drawn a bigger readership. When I wrote the piece on shortstop defense, I received more than 3,000 e-mails from people, and they fell basically into three categories:
There were at least 1,000 e-mails in category 2, and they kept coming in for months after the column actually ran.
This isn't really surprising. If you've had a chance to see a number of Yankee broadcasts over the past four or five years, the announcers have been effusive in their praise of Jeter's defense, and the public at large has had a lot of exposure to him due to the Yankees' domination of the postseason in recent years. Considering this, and the number of media products that have been in front of people's eyes (such as the ESPN: The Magazine cover with Jeter's photo and "Killer D" prominently featured), it's not surprising that people hold Jeter's defensive performance in high regard.
I'm not going to get into the merits and flaws of the various defensive metrics here. We can do that in future columns here at BP. I am going to present some summary data, and I will be more than happy to publish a well-reasoned counter-argument if you want to send one in--and that could certainly include criticism of the metric I'm using here.
So let's get down to it. I asked for some help from Gary Gillette for this column, and he was kind enough send summary data my way for 1996-2000. Mr. Gillette is someone whose work you should seek out, purchase, and read voraciously, and his work is a major part of the inspiration that led to the creation of Baseball Prospectus in the first place. The information and concepts he provided were developed by him and Dave Nichols, and the same schema was later used by Sherri Nichols to create Defensive Average.
The metric I'm using is Adjusted Fielding Range. Adjusted Fielding Range (AFR) is calculated using Adjusted Balls Fielded (ABF) and dividing it by Defensive Equivalent Games (DEQ). AFR=ABF/DEQ.
Adjusted Balls Fielded is a pretty simple concept: when a ball is hit in play, one and only one ball can be fielded. This mitigates the biases caused by putouts or assists that result from events other than fielding batted balls. (e.g. making the tag on a caught stealing.)
Defensive Equivalent Games counts balls hit into play while the fielder was at his position. This is effectively "batters faced" for fielders. This mitigates the biases caused by quality of pitching staffs. If you use innings played as a counter, you miss the extra balls in play as another Paul Wilson Whiplash Shot (PWWS) screams towards the fielders.
A final adjustment is made to normalize for the proportion of left- and right-handed batters faced by each fielder.
Let's take a look at the last five complete years, 1996-2000. The population we're looking at here for these years are all MLB shortstops who started at least 81 games at the position. The chart below shows the average AFR for all shortstops during that season, Derek Jeter's AFR for that season, and, on the right-hand axis, Derek Jeter's Percentile Rank among all shortstops for that season.
In a word, yecch. A lot of people have sent me conjecture that Jeter was injured last year, which is certainly true, and that he's somewhat out of sorts this year as well. It appears to me that while he may in fact be injured, he's never been a good defensive shortstop, and I'll wager that he never will be. To play armchair GM, I wouldn't have traded D'Angelo Jimenez for a generic middle reliever.
It's quite possible that Jeter could be an outstanding defensive third baseman, and that his already excellent offensive performance might improve if he could avoid a few of the nicks and bruises one gets playing in the middle infield. With Jimenez gone and Deivi Mendez disappointing in full-season ball, the Yankees need to hope that Jeter stays healthy, and ends his four-year defensive decline.
Is he likely to end that defensive slide? It doesn't look like it. Through the first half of 2001, Jeter ranks 12th out of 14 shortstops in the AL in Zone Rating, and is dead last in range factor.
This doesn't mean that it might not make sense to continue to play Jeter at shortstop. Derek Jeter is an underrated offensive player. He's displayed every offensive tool there is, and he's just entering his prime. I expect him to have a run of seasons in which he hits something like .325 with 30 home runs and 80 to 100 walks. If you can get another great bat into the lineup by taking that defensive hit, it may well make sense to keep Jeter in there in the six spot. It certainly hasn't hurt the Yankees too badly for the last five years.
Jeter is a great ballplayer, and worth every cent he earns. He's just not a good defensive shortstop.
Gary Huckabay is an author of Baseball Prospectus. You can contact him by clicking here.