With baseball season having arrived, TheLines has prepped some primers on key metrics that can aid your daily handicapping. We’ll continue our dive into pitching metrics, but this time we get a little more granular. Here we look at pitching handedness splits and how you can apply them when betting on Major League Baseball.
What Are Pitching Handedness Splits?
For almost as long as baseball has been a thing, people have been aware that batters have an advantage when swinging from the opposite side from which the pitcher throws. That is, left-handed batters have an advantage against right-handed pitchers and vice versa.
This is known as having the “platoon advantage.” Baseball historian Bill James wrote that platooning – swapping out players in order to maintain the handedness advantage – has been happening since the 1880s.
The reasons behind the platoon advantage are myriad and beyond the scope of this article. What’s important to know is that pitcher handedness splits are very real and can have a large impact on performance.
More key baseball metrics
Why Are Pitching Handedness Splits Useful?
We know pitcher handedness splits are a thing, but they don’t simply exist as a universally, equally applied truth. All pitchers exist on a spectrum in terms of how much these splits affect them.
Some pitchers excel at getting same-handed batters out but struggle with the platoon disadvantage. Others (usually those with tremendous changeups) have minimal splits or even reverse splits.
Knowing where a pitcher falls on the spectrum of vulnerability to opposite-handed (and same-handed) hitters is critical when evaluating how he will do against a given lineup. Ideally, every manager would like to have nine elite switch-hitters to deploy, but reality just doesn’t work like that. Many lineups feature a heavy lean to the left or right side, and certain pitchers will perform better or worse against these lineups depending on their handedness splits.
Using Pitcher Splits: The Case Of Max Scherzer
We all know Max Scherzer is awesome at getting opposing batters out. That’s why he has three Cy Young awards and has already accumulated enough WAR to punch his ticket to the Hall of Fame.
What you may not know is Scherzer actually has a pretty large career platoon split. To see exactly how large, we can head over to his FanGraphs profile. Under the “Splits” tab, we then want to click the “Career” button. When dealing with pitcher splits, we generally want as large of a sample as we can get. Most sources will likely tell you not to completely buy into splits like this without multiple years of data.
In any case, handedness splits are the first ones listed. I’m generally using wOBA (weighted on-base average) as a good “all in one” metric to quantify offense and we can see that Scherzer’s handedness wOBA splits break down like this:
- Left-handed batters: .312
- Right-handed batters: .251
A 61-point split is quite large. For context on where these numbers place the opposing batters, the first one is roughly league-average. Think Dansby Swanson. The second one is worse than Zack Greinke’s career mark. So, the average lefty facing Scherzer hits like a league-average batter while the average righty hits like a very good-hitting pitcher.
FanGraphs also offers a handy page with info for converting these wOBA differences into weighted run values. I’ll save you the math, but this difference works out to almost two runs in a full game’s worth of plate appearances. That’s pretty massive considering the market expects most games to be contested with one or two runs.
Use Pitching Splits To Evaluate Individual Matchups
It’s not super important to get that deep into the math, it’s just important to get a general sense of how handedness splits affect a pitcher. We can see that a righty-heavy lineup is going to be almost helpless against Scherzer while a lefty-heavy lineup at least has a fighting chance.
Keep an eye out for pitchers with big handedness splits because they will perform significantly better or worse versus certain lineups. Also, keep an eye out for pitchers who have had previously large splits that add a pitch during the offseason. This may bring the leap they need to neutralize their splits and become better players.
At the same time, always remember that splits aren’t an end-all for handicapping. Relievers play a bigger role than ever. We should only expect most starting pitchers to play a little more than half of the game. But, bettors who like to wager on the “first 5” markets must remain especially aware of these splits.