How Important Is Defensive Efficiency Rating To Success?


The Tigers just finished the 2012 season as the runner up in all of baseball. While losing the World Series was disappointing, it was obviously a successful season overall. One of the issues the Tigers faced during the 2012 season was its poor defense. It was a concern, not only of ours here at MCB since the signing of Prince Fielder, but many around the world of baseball questioned the Tigers ability in that regard. Our concerns weren’t unfounded as it turns out. The Tigers were well below average defensively throughout most of 2012.

Sep 5, 2012; Cleveland, OH, USA; Detroit Tigers first baseman Prince Fielder (28) advances to third base on an error by Cleveland Indians third baseman Lonnie Chisenhall (not pictured) in the first inning at Progressive Field. Mandatory Credit: David Richard-US PRESSWIRE

Prince Fielder, to put it mildly, isn’t very good with the glove. Not only did his signing mean a poorer glove was manning first base, it put Tigers star Miguel Cabrera at 3B. While Cabrera did a better job there than many expected, it put him and Jhonny Peralta on the same side of the infield, and gave Tigers pitchers infielders with some limited range to say the least. The same could be said for the Tigers corner outfielders.

With bad defenders all over the place, how is it that the Tigers made it all the way to the World Series if defense is so damn important?

The simple answer is that the Tigers pitching staff struck out a lot of batters, meaning less opportunity with balls being put in play. But the real question I am after is, in general, can a team play that kind of defense over the long haul and continue to be successful? Answering that question might yield a different result.

To answer that question, I wanted to take a look at the 2012 playoff teams and their defensive efficiency ratings (DER). In effect, how many teams that play bottom tier defense even make the playoffs? Were the Tigers an anomaly, and should improving the defense be a focus of the organization this off-season?

Defensive efficiency rating is explained on as “Defensive Efficiency Ratio is the rating of team defensive outs recorded in defensive opportunities. To determine Defensive Efficiency Ratio for a team, divide the total number of hits in play allowed (subtracting home runs and times reached on error) by the total number of defensive opportunities (all balls hit into play, not including home runs), and subtract from one: 1-(((H+ROE)-HR)/(PA-(SO+HBP+HR)))”

Essentially, it’s a measure of turning balls into play as outs. While there is no perfect defensive measures out there, I think at the basic level, DER is a decent tool to give us an overall picture.

Of the ten playoff teams in 2012, the Tigers and the St. Louis Cardinals were the only two teams that were in the bottom third of DER. The Tigers were the worst at 26th, while the Cardinals ranked 24th. The world championship Giants? They were middle of the road at 16. Also middle of pack in terms of DER for playoff teams was the New York Yankees at 18 and the Texas Rangers at 15. The rest of the five playoff teams? All were in the top 10 in DER, led by the Atlanta Braves at number three.

What is even more interesting is the make up of the five teams in the top 10 in DER that didn’t make the playoffs. Only Seattle, the most efficient team in baseball last season, wasn’t in playoff contention. Tampa Bay, the Angels, Dodgers, and White Sox, were all top ten defensive efficiency, and all just came up a little short of the playoffs, lending some credibility to the idea that being good defensively tends to be an important part of being a good team.

But taking data from just one year doesn’t make much sense. So I looked at 2011. There was of course only eight playoff teams in 2011. Once again, only two of the playoff teams in 2011 were in the bottom third of defensive efficiency rating, the Cardinals once again, and the New York Yankees. Both teams’ offense made up for defensive deficiencies. Of the other eight playoff teams, four of them were in the top ten, with the Tampa Bay Rays being the most efficient team in all of baseball last year. The other two, the Tigers and Brewers, were right in the middle at 15th and 16th. The two teams that just missed the playoffs on the last day? Atlanta and Boston were good defensive teams as well.

2010 was even more telltale. Of the eight playoff teams in 2010, six of those teams were in the top 10 in DER for the regular season, with Atlanta and Minnesota being in the middle of the pack at 14th and 16th respectively. There was no team that made the playoffs in 2010 that was in the bottom third of DER.

While this isn’t the most scientific of studies, and not the most scientific of stats, that’s not necessarily what I was going for. I think what is clear, is that in general, defense is an important aspect of successful teams. If we total the number of teams that were in the bottom third of baseball in DER that last three years that made the playoffs, we get four. Four out of 26 teams I think speaks to that importance defense means to a team.

Can poor, or even mediocre defensive teams win in the playoffs? Of course they can. The Giants and Cardinals have proved that the past two seasons. Though it should be pointed out that both of those teams DER ratings increased significantly in the playoffs when they won the World Series. And we all saw how the Giants defense helped them beat the Tigers in the World Series this season.

I think it is safe to say, playing good defense is important. The Tigers could certainly stand to improve it to get better in 2013, and it should be a focus of Dave Dombrowski and company. Either that, or they are going to have to improve their offense to the point that it makes up for it. But as we saw with 2012, we can’t exactly count on that.