When is the last time you sat down and analyzed a Major League Baseball team’s defense? The answer is likely either a long time ago or never. The average sports bettor thinks a lot about defense when analyzing a football or basketball game, but I’m convinced that most people don’t think nearly enough about defense when it comes to baseball. It may not mean as much as the starting pitching matchups, but in a sport where many games are decided by a run or two, defense is definitely worthy of your attention.

How many times have you seen an infielder boot a routine ground ball, which leads to a big inning? I know I have seen this happen many times. What about the other side of the equation? Think of all the times that you have seen someone make a terrific play in the field to save a run or multiple runs. The best managers in baseball will tell you that it is next to impossible to win without a solid defensive team.  

MLB Betting: Disparity in Defense Examples in 2011

The 2011 season is only a little more than a month old, but there are already some impressive statistics panning out. The St. Louis Cardinals and Texas Rangers lead the league in errors with a total of 28 so far this year. Should it really surprise us, then, that the Cardinals and Rangers have been good to ‘over’ bettors? The ‘over’ is 20-11-1 in the Cardinals 32 games so far in 2011. The ‘over’ is 17-13-1 in the Rangers 31 games. On the other end of the spectrum, the Tampa Bay Rays have just 12 errors so far this year. Bettors who have been playing the ‘under’ on Rays games have been rewarded very nicely. The ‘under’ is 21-10 in the Rays 31 games this year. Interestingly, the Rays have been particularly impressive on defense at home, where the ‘under’ is 15-4 in their 19 games.

In past years, the differential between a good defensive team and a bad defensive team has been quite staggering. In 2009, the Washington Nationals committed 143 errors. In that same year, the Pittsburgh Pirates committed just 73 errors. A difference of 70 errors over the course of a season is definitely statistically significant. While the Pirates weren’t a good team in 2009, they did keep the games close and low-scoring in most cases because of their solid defense.

MLB Betting: Should It Really Matter if the Run is Earned?

One area that I believe receives far too much attention is the earned run. Most bettors look only at earned runs when evaluating a pitcher, but I believe the unearned runs should be taken into account, especially on consistently bad defensive teams. At the end of the day, your bet will be graded by the total number of runs scored by each team, not the number of earned runs. Consider taking unearned runs into account more the next time you place a wager.

MLB Betting: How to Take Advantage of Defensive Statistics

If defenses are so important when it comes to betting on baseball, how should you take advantage of the defensive statistics you find? There are a couple of areas where knowing these numbers should help give you an edge for baseball handicapping. First of all, look for games with two bad defenses, and consider playing the ‘over’. Chances are high that in a game between two poor defenses there are going to be some cheap runs scored. In the same manner, the ‘under’ is often worth a look when two solid defenses square-off. While totals may be the easiest area to profit on defensive statistics, I believe the runline is another area that can be successfully used by wise bettors. In this case, look for a matchup between teams who are polar opposites on the defensive efficiency spectrum. The -1.5 runline holds some extra value when betting against a team who has a poor defense. Similarly, the +1.5 runline is often a value when betting on a team that plays exceptional defense. Keep a close eye on those defensive numbers, and look for opportunities to find some extra value!