Defensive metrics are in their infancy. Compared to offensive statistics like RC/9 (runs created per nine innings) or OPS+ (on-base percentage plus slugging percentage relative to the league average), statistics that rate how well a player plays on defense are well behind the curve. That said, there have been a number of recent advances in defensive metrics that shed significant light on team defenses, as well as that of specific individuals.
Rate2 is a metric popularized by Clay Davenport. Essentially, it measures the amount of runs per 100 games a player is above average at his position. If a player is a 110 at shortstop, he saves his team 10 runs more than the average shortstop for every 100 games he plays. If a player is an 85 at first base, then he costs his team 15 runs more than the average first baseman for every 100 games he plays. This statistic is also normalized for league difficulty and over time.
This past year, another metric was introduced by John Dewan and Baseball Info Solutions in The Fielding Bible. Known as the plus/minus system, it is essentially an upgrade on the popular Zone Rating system. By breaking down the entire field into vectors and scouting video of every ball put into play over the season, John Dewan and his BIS cronies were able to determine how likely any ball in play was to be fielded. One example Dewan gives is that slowly hit balls into Vector 17 (between the shortstop and third baseman) were turned into outs 26% of the time. If a shortstop makes a play there, he is credited with +0.74 (1 - 0.26). If he fails to make a play, he is credited with -0.26 (0 - 0.26). After every single batted ball is tallied, each player will have a total number of plays that they made above or below the average player at their position (represented by 0). Obviously, adjustments are made specific to each position.
Individual plus/minus ratings will not be available until sometime in the off-season. However, team plus/minus ratings are already available. The Orioles came out at -24 on the season. They were 24 plays above average on flyballs, but 50 plays below average on groundballs. They were also 11th out of 14 American League teams in terms of defensive efficiency, or the rate at which they convert batted balls into outs. Let's try to explore where the problem lies.
Kevin Millar made the majority of starts here for the Orioles. In 98 games, he posted a surprisingly good 105 Rate2. Even more surprisingly, this is actually in line with previous performances, despite his less inspiring reputation. The plus/minus system concurs, rating him around average on balls to his left, right and directly at him in 2005. He was given a D+ grade in terms of fielding bunts, but he got an A+ in 2004. Chris Gomez played 27 games a first base and was exactly league average according to Rate2
After a 107 mark in Rate2 in 2005, Brian Roberts dropped to a slightly below average 98 in 2006. The plus/minus system had Roberts as one of the better second basemen in baseball in 2005, rating him above average at balls to his left, right and directly at him. Perhaps the elbow injury played some role in his declining defense as well.
Melvin Mora had a decidedly mediocre year. Despite his newfound wealth, Mora had his worst season yet at third base. His 86 Rate2 was nearing the unacceptable level. In 2005, his defense was rated a more manageable 96 according to Rate2 and almost league average according to the plus/minus system as well. Unfortunately, he was given a D- grade for handling bunts, performing worse than 25 other third basemen.
Miguel's defense is something of a talking point in these parts. He has all the tools, including one of the best arms in baseball, but his apparent lack of hustle makes many think that his defense is below average. Not so, according to Rate2, which has him at 104. The plus/minus system is roughly in line with this. He rated as the 13th best shortstop in baseball in 2005 and the 4th best in 2004. Tejada's defense is likely to regress as he heads down the wrong side of thirty, but his deficiencies thus far have been greatly exaggerated.
Catchers are not rated according to the plus/minus system because it would be impossible to do so accurately given their methodology. However, Ramon Hernandez has quite a defensive reputation. Rate2 has Hernandez at a slightly disappointing 101, which is in line with his previous performance, but that's still solid.
Brandon Fahey played 53 games in left field. Read that sentence again. Chances are that if you're not from Baltimore, you're laughing by now. Anyway, Fahey had a respectable 98 Rate2 in his first exposure to the position, which is more than can be said about the corner outfielder's batting line. Fellow rookie Nick Markakis had an impressive 110 Rate2 in 26 games in left field.
Corey Patterson had another solid year, turning in a 102 Rate2 in 134 games in center field. The plus/minus system has him right around average from 2003-2005. With his speed and strong arm, O's fans seem to be under the impression that Patterson is a gold-glove caliber outfielder. Apparently, this is not the case. Although, a league average center fielder still has plenty of defensive value.
Nick Markakis was excellent in the field, even as he struggled offensively early in the season. His 105 Rate2 underscores his potential, as the 22 year old adjusted to several new ballparks in his first major league season. With the prowess he demonstrated in left- and right field, some in the organization are convinced that he might eventually force his way into some action in center field.
The only obvious liability in the field is Melvin Mora. In fact, his defense was bad enough this year that the Orioles would be well served to consider shifting him off of the hot corner permanently. Unfortunately, this year's free agent market lacks any impact third basemen and the Orioles have bigger needs to address. Mora alone is not enough to account for all of the gap between the Orioles' and the average American League team's defense, but other areas of concern are less dire. For instance, it is quite possible that Roberts' decline is related to his off-season elbow surgery and it's likely that, similar to his power, his defensive numbers will rebound the further he is removed from it.
Michael Hollman is the Senior Writer for Inside The Warehouse and can be reached via email at Publisher@InsideTheWarehouse.com