Among members of the traditional baseball community, lineup protection is a well-accepted truth. Among many members of the sabermetric community, lineup protection is a myth. Both can’t be right, but I’m sure not sure we know which side is.

First off, let’s define the term. Lineup protection is the idea that the hitter who hits behind you impacts how you perform based on a pitcher’s willingness to attack the zone against you versus pitching around you to face the next hitter. Let’s go a little further.

1) Protection assumes that it is better for Hitter 1 to see pitches in the strikezone because those pitches are easier to hit, therefore, protection increases your offensive numbers that do not include walks.

2) Protection assumes that a pitcher has some ability to control whether or not they throw you strikes versus balls in an at bat.

3) If you are “protected” you will see fewer pitches outside the strikezone, thus giving you a better chance to produce offensive numbers.

Now the sabermetric community points to evidence that says protection is myth because it hasn’t been shown to matter in any of the cases in which it could be tested. But a reasonable person would point out that to conduct a valid test, we would have to control for factors that we cannot control for in real life. We can’t randomly assign pitchers. We can’t hold the quality of the Hitter 1 constant. Even if you try to do that in a statistical sense, the sample size gets too small to have findings of any real significance.

The sabr crowd will tell you that the absence of evidence for protection means the burden of proof is place on those supporting it, and that’s a fine request in the abstract, but my aim isn’t to litigate an argument, it’s to see if protection is a thing or not.

More specifically, I want to see if protection should exist. In other words, should the hitter behind you impact how you get pitched?

I argue that it should and I’ll lay out my reasoning here. I can’t present an argument that protection does happen because it would be impossible to show that it does while maintaining a valid design, but I can present the argument that protection should exist using the 2012 Detroit Tigers.

Our Hitter 1 in this design is Miguel Cabrera. In 2012, Prince Fielder hit behind him and “protected” him. I will use their 2012 stats to craft their abilities, but these numbers could be adjusted if you prefer to track likelihoods by career numbers, monthly numbers, etc. Does Fielder’s presence behind Cabrera change the way a pitcher should attack Cabrera? I argue that it should.

Let’s look at this in the simplest terms possible. No one on, no one out. Cabrera leads off the inning, Fielder due up second.

In this scenario, Miguel Cabrera will get a base hit 33% of the time if the pitcher does not walk him (assuming Cabrera doesn’t know the pitcher will choose not to walk him). Fielder will get a base hit 31.3% of the time under the same conditions.

But not all base hits are the same. A walk and a single in this scenario have the same outcome for Cabrera, but doubles, triples, and homeruns are more damaging. Here, the pitcher would choose to walk Cabrera in all cases in which he would get a hit that wasn’t a single.

.33(batting average)*.41(% of hits that are for extra bases) = .1353

Regardless of who hits behind Cabrera, 13.5% of the time it is a better choice to walk Cabrera instead of pitching to him. If you don’t walk Cabrera, he will get an extra base hit 13.5% of the time, so you should walk him in those cases, but the other 86.5% of the time he will make an out (better) or single (equal).

So now let’s introduce his protector. Fielder gets a hit 31.3% of the time and 35% of his hits are for extra bases. This is important here because if Fielder gets an extra base hit, it is irrelevant what Cabrera did. If Cabrera gets a hit and then Fielder doubles, triples, or homers, Cabrera will score regardless of what base he occupied.

What we care about is how often Cabrera will get an extra base hit minus how often Fielder gets an extra base hit. We want to know how often we should walk Cabrera, so we need to see how often a Cabrera extra base hit will be followed by a Fielder single or out because a Fielder extra base hit would score a Cabrera walk.

Piece this all together and we discover that with none on and none out with Cabrera leading off and inning with Prince protecting him, walking Cabrera is the preferred choice 2.5% of the time.

This tells us that when Cabrera leads off an inning, 97.5% of the time, pitching to Cabrera will be the same or better than walking him with Fielder behind him. Obviously you can’t predict which 2.5% it will be, so you play the odds and always pitch to him when he leads off an inning.

How does this help us solve the problem? Should lineup protection matter?

It helps because if we insert the 2012 version of Delmon Young into this methodology, we should walk Cabrera 5.5% of the time. This still doesn’t tell us to walk Cabrera when he leads off an inning, but it tells us that we should walk him more to lead off an inning with Young behind him than if Fielder is.

This tells us that protection should matter. The hitter who bats behind you should impact the pitches you see. In practice, the likelihood of a walk being a smarter play with Young behind Cabrera means a pitcher should be more willing to pitch around Cabrera than if Fielder was behind him.

This becomes more evident when you add in baserunners and outs. I’m not going to walk through all the math in each of the 24 possible arrangements except to say that the more baserunners there are, the more valuable a walk can be over a hit. If a runner is on 2^nd base, a walk is better than a single in the pitcher’s eyes, so the percentages slide in favor of a walk. However, you’re making a trade off because you are saying you like a 31.3% chance of a hit to a 33% of a hit when it comes to scoring the runner from second, but you are risking the chance that Fielder drives in Cabrera too.

The point of this entire piece is that the hitter behind Cabrera should matter. A pitcher should be more willing to pitch around Cabrera based on who hits behind him. That is hard to ignore, even if the percentages favor pitching to him in all scenarios. The important take away, however, is that it should also be a matter of degree.

Fielder and Young are dramatically different hitters. A very good hitter like Fielder matters over someone like Young, but would Fielder matter of Victor Martinez? Glad you asked.

Victor behind Cabrera means you should walk Cabrera 3.9% of the time in our scenario. So Prince is a better protector because he hits for extra bases more than Martinez does. But the difference is smaller than when Young is involved.

So, protection should matter, it’s a question of how much. A better hitter should protect you more than a lesser one and one who hits for more power should protect you more than one who hits more singles. It’s a sliding scale, so an overall difference would not be that evident unless the two potential protectors are significantly different both in reality and in the minds of the pitchers.

So while I cannot prove that protection exists, it absolutely should exists and should favor hitters with higher averages who get a lot of extra base hits. Additionally, since most baseball people believe it exists, that should reinforce its effect.

It should have a larger effect when pitchers and managers believe it exists. If they change their approach based on who hits behind someone because they believe it matters, then it will matter. Since it also should matter in a formal, logical sense as shown above, there is no other belief except to posit that lineup protection is a real thing, even if we can’t prove it.

The sabermetric response to this finding would likely be that even if it varies based on who hits behind you, the percentages always favor pitching to Cabrera over walking him. In other words, we never break 50.0%. This is true, but it misses something important. If 95% of the time you should pitch to Cabrera (and this is the extreme end), 1 out of 20 times, you should have walked him. This should impact you approach as a pitcher or you are being irrational. You should be more willing to walk Cabrera with Young behind him than Fielder even if your preference is to never walk him.

Protection should and probably does exist, even if the results are relatively small. Cabrera will not have a dramatically different season with Fielder or Young behind him, but we should observe differences, which means protection is likely a real phenomenon.