Factor Run Differential into Your MLB Bets

Last year, five Major League Baseball teams had run differentials of +100 or more. All five made the playoffs. Six teams were -80 or worse in run differential, and each lost at least 89 games. The data from 2012 and 2013 is similar.

The moral of the story? Run differential is a great predictor of success.

With the season about one-quarter complete, what can we learn, and how do we take advantage of it?

Bringing to your attention that the Royals, Cardinals, and Dodgers are doing very well is not all that helpful. They are established as good teams and there is no great value in betting them. The same can be said for the Phillies, Brewers, and Rockies. They aren’t fooling anybody into thinking they are underachieving, and there’s little value betting against them right now.

But there are opportunities out there if we’re looking at run differential, specifically in the American League West. The Astros are off to a very good start and their run differential is commensurate with their record. However, based on runs scored and allowed, the rest of the division is a crap shoot.

The Angels and Rangers, who are both hovering around .500, have what you would expect: run differential margins almost at zero. The Mariners, however, are also near .500 yet have an ugly run differential margin, while the A’s have one of the worst records in the league but are almost at zero themselves.

This is a clear indication Oakland is underperforming, and Seattle is overachieving. Everybody knows Felix Hernandez and Sonny Gray are really good, but when anyone else is pitching, going against the M’s and with Oakland has sound reasoning behind it if their lines are based on their records.

The AL East also has numbers that can benefit smart bettors. The Red Sox record is much better than their run differential numbers, and the Blue Jays should be a lot better than their current mark. There is really no reason the Sox should be playing .500 ball on the road and, given the right match-ups, betting against them outside of Fenway is advisable.

Toronto is a bit more complicated. Their pitching is a mess. However, if you believe Mark Buerhle and R.A. Dickey have just gotten off to slow starts and will eventually be near their career averages, I’d be playing them almost every time they take the mound.

The only real outlier in the National League is the Pirates. They should be better than their record. The last two years plus their run differential in 2015 lead us to believe they will be very competitive moving forward. Pittsburgh is about to start a ten-game road trip. Watch it carefully and pick your spots. If they are playing well when they get back to Pittsburgh, there is a good chance they’ll beat up on Milwaukee, Philadelphia, and the White Sox.

Again, betting blindly on run differential is not advisable. Though it is likely to yield winning percentages that are positive, they may not cover the vig. However, picking your spots while using it is as a piece of your handicapping puzzle makes a lot of sense.

(Photo credit: Keith Allison (flickr) [https://creativecommons.org/licenses/by-sa/2.0/legalcode].)