OPS: The Most Valuable Hitting Statistic

Yankees' OF Aaron Judge; Photo via Keith Allison

One of the more interesting stats of the day, OPS seems to be a bridge of sorts between today’s advanced stats (wOBA, xwOBA, wRC+) and the old, basic stats of baseball (BA, OBP). This bridge, the simplicity of the stat, and the ease at which it can be used to evaluate players make it the premier offensive metric.

What is OPS?

OPS has been around for much longer than most people know. It was first drummed up in 1979 but did not immediately become widely used. Baseball has a long history of being against change, so it makes sense that such a common and important statistic in today’s game took a while to first catch on.

Before examining why OPS is so valuable, it needs to be quickly explained. OPS stands for “On-Base plus Slugging” which simply means on-base percentage plus slugging percentage. On-Base percentage is as described, the percentage at which a player gets on base. Slugging is a little more difficult but still easy to digest. It is the number of bases a player hits for per AB. If a player's SLG is .650, then, on average, they hit for .650 bases per AB. Adding these two stats together gets you OPS.

That is easily understandable, and most baseball fans are familiar with OPS. What most fans aren’t familiar with is that OPS is an all-encompassing stat that can give a complete picture of a hitter’s ability. Before OPS, batting average was considered the most important hitting stat, but it has clear holes. First off, batting average completely ignores walks, which can be a big part of a hitter’s game and are a very important part of hitting. It also completely neglects power, and there is no way of knowing a player's extra-base hit capabilities by looking at his batting average. OPS eliminates both of those flaws and shows how often a player gets on base and the power a player exhibits.

How to use OPS correctly:

Just like any other stat, OPS must be used correctly in order to properly evaluate players. For instance, OPS can be viewed from two different angles. It uses two other stats in its computation, which can lead to some ambiguity when comparing players. There can be two players with similar OPSs who are very different hitters. For example, in 2022, Corey Seager and Steven Kwan had the exact same OPS at .772, yet they were completely different hitters. Seager’s .772 resulted from a very high SLG, thanks to 33 HRs and a great power swing. Kwan’s .772 was boosted by his 62 walks and .373 OBP, not by power numbers. One could look at these two OPSs and assume Seager and Kwan are similar hitters, but that could not be further from the truth. This is why it is important to use OPS in the correct context.

Another issue in the use of OPS is trying to set a baseline for hitters that they must reach in order to be considered successful. For example, I heard a college coach say that his hitters have to get to a .800 OPS to be good for the season. This mindset needs to be changed, as OPS, despite its merits, is not the end-all, be-all baseball statistic. As seen with my Seager and Kwan example above, hitters can be very different but still produce value. Every hitter is different and should focus on what makes him good. A high OPS will follow. Having a baseline OPS as a goal could possibly make a hitter do stuff that is not a part of their game. If Steven Kwan, for example, decided his OPS wasn’t high enough and tried to increase it by hitting for more power, that will likely hurt his plate discipline and elite OBP. The most likely result of that scenario is a counterproductive decrease in Kwan’s OPS. Hitters need to focus on and create their own skillset without using OPS as a specific goal.

Why OPS is ultimately extremely valuable:

OPS is a vital stat in baseball today and will be for years to come. It is one stat that anyone can look at and understand easily, and it is one of the few stats out there that can show a hitter’s on-base and power abilities in just one number. On top of this, OPS is a very easy stat to understand and calculate, making it applicable across all levels of baseball. When used and understood correctly, it is the best stat for any fan to evaluate hitters.

Sources:

Baseball-Reference.com

SABR.org

"Aaron Judge in 2017" via Keith Allison licensed under CC BY-SA 2.0