Born when I was, I grew up measuring hitters by the traditional Triple Crown stats: Batting Average, Home Runs, and Runs Batted In. Those were stats that were easy to understand and were available in any box score.

The Sabermetrics Revolution started by Bill James and others introduced more “advanced” stats over the years like WAR, WRC+, and OPS. Today I want to take a deeper dive into this latter stat.

OPS stands for On-Base Plus Slugging. Here is the formula for figuring out OPS:

I don’t know about you, but when I see this kind of math my eyes glaze over. What is most important to see in this formula is that OPS tries to account for most of the ways a player gets on base (H=hits, BB= walks, HBP= hit by pitch) AND it tries to weight the value of hits by counting the players Total Bases (TB) and giving credit for Sacrifice Flies (SF). By doing that, it ends up giving more weight to power hitters than to singles hitters.

The OPS formula results in a decimal number measurement for each player. It is a stat that tv and radio play-by-play people, and now some ex-players, will often use these days. As a general rule. here is a table to help you interpret the numbers.

Category	Classification	OPS range
A	Great	.9000 and higher
B	Very good	.8334 to .8999
C	Above average	.7667 to .8333
D	Average	.7000 to .7666
E	Below average	.6334 to .6999
F	Poor	.5667 to .6333
G	Very poor	.5666 and lower

Here is the top ten single-season performances in MLB history. All are left-handed hitters:

• Ted Williams, 1.2566 (1957)
• Barry Bonds, 1.4217 (2004)
• Barry Bonds, 1.3807 (2002)
• Babe Ruth, 1.3791 (1920)
• Barry Bonds, 1.3785 (2001)
• Babe Ruth, 1.3586 (1921)
• Babe Ruth, 1.3089 (1923)
• Ted Williams, 1.2875 (1941)
• Barry Bonds, 1.2778 (2003)
• Babe Ruth, 1.2582 (1927)

Here is the thing with OPS that I have discovered. As a baseball fan, I am less and less interested in power hitters. I find myself focusing more on players who bunt and guys that put the ball in play and are good on the bases. For that reason, most of my favorite players these days do not show up in OPS leader boards.

Let’s take a look at one of my all-time favorites, Rickey Henderson. Rickey finished his career with an OPS of .820. According to the chart above, that would translate to an “above average” career. Also, due to the way that OPS is figured, the aging Hall of Famer’s twos highest OPS seasons were his final two seasons, when Rickey was still drawing walks and stealing bases but not at the clip he had been earlier in his career.

Obviously the idea that Rickey Henderson was merely Above Average is absurd. He is one of the greatest players of all time after all. Is OPS a bad stat then? No, OPS like any baseball stat is just one flawed place to begin looking at a particular player.

OPS factors in walks and Rickey was great at getting walks. He even led the league in walking four times. But for a walk, the OPS formula only gives him one Total Base. Rickey stole 1406 bases in his career. That is 1406 bases that the OPS formula cannot and does account for. And for peak Rickey Henderson, a walk to first could easily become a double or triple.

So next time you hear an announcer talking about a players OPS, consider what is being measured and is not being measured. Think of players like Rickey Henderson that cannot be measured by OPS or any other stat.