The Beauty of the On-Base Percentage

At some point in our time around the game of baseball, all of us have heard a coach use the phrase “the best hitters in baseball make outs 70% of the time.” This is actually incorrect. They are obviously referring to the notion that the best hitters in baseball usually hit around .300, and that is indeed accurate. They do. However, they most certainly do not make outs 70% of the time.

Take for example Andrew McCutchen in 2014. Accounting for all his plate appearances, it would be far more accurate to say that he made an out about 59% of the time (we are not including the number of times he reached on an error for our purposes here).

Want a more extreme example? Barry Bonds in his 2004 season actually only made an out 39.1% of the time!

This notion may be surprising, and we must clarify that we are by no means saying McCutchen hit .410 this year or that Bonds hit .609 in 2004. This actually reinforces the idea we were presenting in our previous article about how the batting average is a misleading statistic.

What we are trying to present however, is a more accurate measurement of just how often players get on base, as well as how often they don’t make outs.

So as we begin discussing the On Base Percentage statistic, keep in mind its actual calculation:

OBP=(Hits+Walks+Hit by Pitches)/(At-Bats+HBP+Walks+Sacrifice Flies)

Simply put, the OBP stat tells us exactly what you probably think it tells us: the rate of how often a hitter actually reaches base. The reason this is important is statistically very simple: base-runners correlate to runs, and runs correlate to wins.

I’m sure every single coach out there can reassure our belief that you do not win games by hitting six or seven solo home runs. On the contrary, you get runners on base to create run scoring opportunities, and then mix in extra base power and speed to your offensive game. That is the very definition of a dynamic offense. Take the ten teams who made the playoffs in 2014: 7 of them were ranked in the top 10 in On Base Percentage, a trend you will find no matter what year you look up.

Many baseball minds who love the OBP statistic love the base on balls. We would like to clarify that we are not discussing a hitter’s ability to take a walk, so much as we are discussing his ability to get on base. There is indeed a slight difference.

If you look into the calculation of the metric, you immediately realize that walks and hits are the two inputs that a hitter is most in control of, as you never want to rely on a player being a valuable offensive weapon because of his ability to get hit by a pitch.

At the end of the day, we advocate that there be separation between the batting average and the OBP. In other words, we never want to undermine a player’s ability to make hard contact and get hits, but we understand walks are most certainly important as well as very projectable (it’s rare to find a hitter whose eye at the plate just disappears).

Beyond just getting on base, walks imply a very patient hitter, which also hints to the fact that the player is swinging at hittable pitches and not pitcher’s pitches. We will look into the importance of this when we discuss the Slugging Percentage statistic.

No matter who you are coaching, your message to your hitters should always be the same at its core: get on base. Some players will have a gifted ability to make hard contact on every swing and hit .325, so they won’t have to walk much to achieve a respectable OBP. Other’s may only hit .260, but still possess an elite OBP (around .400 at the Major League level) because of their keen eye at the plate.

As a coach, you should mainly be concerned with whether or not your hitter is avoiding making outs frequently, and not so much the process of how he does so. A walk isn’t necessarily as good as a hit, but a base runner is a base runner. You can’t score a run if you don’t get on base, and you don’t win games if you don’t score runs.

On that merit alone, the OBP is absolutely one of the most important (yet simple!) offensive measurements in the game today.