Last week, we looked into The Shift and whether it was actually doing what we said it was supposed to do, which is to be a better way of getting hitters, especially pull-happy hitters (and double especially groundball-heavy, pull-happy, left-handed hitters) to make more outs. The traditional story of The Shift is that because those hitters are going to be sending most of their ground balls to one side of the field, why not put more fielders over that way?

But an interesting thing happened when we looked at the numbers. I found that players actually had a (slightly) better BABIP, though a (slightly) worse SLG on contact in shifted plate appearances than we would have otherwise expected by looking at their BABIP in non-shifted situations. That means that The Shift was actually producing fewer outs than we might have expected than the non-shift baseline. Now, that’s in the aggregate and league-wide, but it’s surprising for something that’s supposed to be a net positive. Doing a little more research, I found that in shifted situations, hitters produce more grounders than we might expect of them and go oppo (slightly) more often than we would expect. The Shift might be better at gobbling up the grounders that are hit, but it won’t get all of them, and some of those grounders would have otherwise been flyballs, which are much easier to catch. The net effect is at best neutral.

It’s a piece that has provoked some strong reactions. No less a luminary than Ben Jedlovec of Baseball Info Solutions (who provided the data that I used in my original work) proposed that one flaw in my research methodology was that because I set my minimum inclusion criteria at 100 non-shifted PA’s in the year in question, it left out the players who got shifted the most. David Ortiz doesn’t get 100 non-shifted PA’s in a season, so he’s de facto left out of the sample, and he might be the quintessential shifted player.

Mr. Jedlovec essentially duplicated my methodology, but relaxed those inclusion criteria a little bit and found a (small) net positive effect for The Shift when it comes to BABIP. His methodology makes sense, although I think it’s telling that the Shift’s positive effects can only be re-established when the most “shift-able” guys are thrown back into the mix. It seems that what we have are some guys who are very shift-able (hello, Mr. Ortiz!) and when they are taken out, The Shift becomes a net negative. I take that to mean that teams shift against far too many hitters. It’s not that they should take The Shift off for everyone, or even for everyone except the David Ortizes of the world, but overall, there are a lot of shifts that are being done that are actually counter-productive, if only slightly so.

And then there’s this. These are analyses that I conducted last week, but didn’t publish (mostly for the reason that the piece was already 3,000 words long by the time I got there.)

I should probably…

Warning! Gory Mathematical Details Ahead!

I essentially ran my analyses from last week backwards. I looked at all hitters who had been shifted against at least 50 times during the year in question. This will most certainly get the guys who are heavily shifted into the sample. I looked at their shifted stats as my baseline and looked at what happened when they weren’t shifted. Again, this is summed across the entire league.


No-Shift Hits (expected)

No-Shift Hits (actual)

No-Shift Total Bases (expected)

No-Shift Total Bases (actual)


























In this case, if The Shift really is superior, we should see that when teams switch to an inferior defense against these same hitters, they should increase the number of hits that they get compared to expectations. And they do. In odd-numbered years. The overall effect is (slightly) net positive toward the defense, but not the kind of numbers that would make anyone stand up and cheer. At the very best—in the aggregate and as the shift is practiced now—The Shift is a net neutral when it comes to defensing balls in play.

We’re used to looking at the list of teams who shift the most and patting them on the head for being so forward-thinking. They may very well have been the teams that initially found the magic hammer but, it seems that they have made the mistake of running around and using it to pound all of the existent and non-existent nails that they see.


When I opened the piece last week, I began it with what I referred to as a “cheeky question” which was how many home runs had been hit against The Shift. It seems like a silly question because if the batter hits a 500 foot blast, there’s nothing that The Shift is going to do to bring it back into the park. But still, I wondered whether The Shift might make pitchers throw differently, perhaps “taking away” one of their pitches or a location and making the pitchers more predictable. That might make it easier to tee off on him. Maybe strikeouts and walks would also be affected.

The way that the data which are publicly available are set up, there’s no accounting for any ball that isn’t in the field of play.

Enter BP reader Brad McKay who e-mailed me and had a rather interesting way to look at the issue:

Following up on your work, I looked up the most frequent shifters since 2012 on FanGraphs. First, I ran a quick zero-order correlation with team HR/FB rate over the same period. Surprisingly (to me), there was a significant positive relationship between total batters faced with the shift and HR/FB rate. Just in case teams in hitter-friendly parks were more likely to shift, I controlled for each team's home HR park factor. Park factor was not significantly related to TBF with shift, and TBF with shift explained even more remaining variance in HR/FB after controlling for park factor.

Here's a summary for the results:

Zero-order correlation:

TBF with shift and HR/FB, r = .383, p = .03

Park factor, r = .721, p < .01.

Multiple Regression (partial correlation):

Park Factor, r = .728, p < .01

TBF with shift, r = .407, p = .03

Worth wondering if teams actually do give up more home runs when they shift… Maybe hitters are adding lift to their swing instead of hitting groundballs the other way.

He later wrote to say that he did not find any association between shifting and strikeouts or walks, using a similar methodology. Now, this most certainly isn’t bulletproof evidence that shifting increases the likelihood of a home run, but it is at least directional evidence. It could simply be a random fluke. Maybe there’s some other factor that links teams that shift with teams that give up a lot of home runs. Maybe the teams that aren’t very good tend to shift a lot. And give up a lot of home runs. But we do know that even the best-case version of The Shift leads to only very modest gains for the shifting team, and we have as yet not fully accounted for the balls that are not in play. If the home run finding is true, it could very easily wipe out the minor gains that come from The Shift’s magical BABIP properties.

The ‘Why’ Matters
If you look at The Shift in a vacuum, it would seem entirely obvious to work. If you assume that everything would work the same whether The Shift was on or not, you’d be a fool not to put The Shift on. But I’d submit that everything doesn’t work the same when The Shift is on. Paradoxically, understanding “why” might be the key to saving The Shift.

Let’s begin with the assumptions that pitchers are human and are aware of what’s going on in the infield behind them. While The Shift may be mathematically a great idea, it is also… well… weird. I think that if The Shift had been present since the 1920s, it would likely work just fine. But broadcasters still make a point of mentioning The Shift because it’s still a little strange. Notice that they never bother to say “two on the left, two on the right” because that’s the default that no one questions.

Now, put yourself inside the head of the pitcher. I doubt seriously that pitchers object to The Shift because they don’t get the basic underlying math. It’s not that hard to explain. But what’s harder to shake is the mental baseline that he has to deal with. He will always be able to look at a groundball and say “Well, against a normal infield, that would have been…” In some cases, the answer will be “that would have been an out.” (Boo.) In others, the answer would be “that would have been a hit“ (Hooray!).

People are loss-averse. The “pain” that comes from losing something that one “should” have had (the ball that squirts through the left side because Ortiz went oppo and poked it right past where the shortstop would have otherwise been) is greater than the “pleasure” that one gets from getting something that one did not previously have (the grounder that is hit right at the strangely placed shortstop that otherwise would have skipped into center field.) The fact is that both grounders represent roughly the same value (an out turned into a hit vs. a hit turned into an out), but the emotional value is higher in the first case.

And so, maybe without even noticing, pitchers might begin to shade their pitch selection to avoid anything that might result in an opposite-field hit. (This would make a fascinating study!) This sorta makes sense for practical reasons, although the entire reason that the Shift is on is that when the infield was played 2-and-2, the hitter didn’t normally go oppo.

Indeed, maybe the pitchers are just trying to be accommodating. The most obvious thing on the field when The Shift is on is… The Shift. It’s meant to help out when Ortiz hits a groundball, so I’d better go and get a groundball, rather than go get an out. I need to do this to help my manager justify himself for calling such a weird defensive formation. So much of pitching is in the element of surprise. Hitters are always looking for ways in which pitchers tip their pitches. In this case, they might fall into patterns that make them easier to read. Sometimes you don’t need to look for the slight tilt in the left arm. Just count the number of guys to the right of second base. What do you do when The Shift is actually a “tell?”

If teams want to continue shifting, then it will require a deep look under the hood to see whether their pitchers are falling prey to these natural inclinations. Are they prioritizing the wrong things (loss aversion? pitching for grounders rather than outs?) when coming up with a strategy to deal with this hitter? How to handle the very real (and yes, unjustifiably out-sized) sadness that comes from giving up a hit that a normal infield would have turned into an out. Not just on an after-the-fact basis, but for the fear of it happening. Essentially, you need pitchers who are willing to use all their tricks, even in a Shift situation and even the tricks that might be a little more likely to lead not just to a hit, but a hit that might be the fault of The Shift.

In 10 years, if shifting continues, and teams continue to introduce the idea of shifting even in their minor league affiliates, then perhaps we might see that the pitchers raised in this ecosystem won’t show some of these issues, but until then, it’s worth wondering whether teams shouldn’t shift their focus elsewhere in trying to scrape a strategic advantage. It’s not clear that The Shift is really doing much for teams now.

Thank you for reading

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When you compare shifts to no shifts for batters, how are you controlling for pitcher, park, game situation, etc.?

It is likely that when batters are shifted or not shifted, they face a different pitcher, park, defense, game situation, etc. in each bucket and there is no reason to think that those differences are not biased.

For example, some teams heavily shift and others do not and the pitching, park, and fielding of those teams that shift a lot are probably not equal to that of the teams that don't shift a lot.

And why do you keep focusing on BABIP (and slugging) and then trying to conclude whether shifting is good or bad?

Shifting clearly will impact HR, K, and BB (regardless of what Mr. McKay found) because clearly batters and pitchers will change their approach with and without a shift (they SHOULD change their approach).

We can't conclude whether shifting is effective or not (or roughly a wash as you keep saying) without looking at a comprehensive stat like wOBA, right? In terms of "effectiveness" we don't really care how it impacts BABIP or some other subset of offense. We only care about how it impacts overall offense, right? If it increased BABIP but it decreased wOBA because batters were going the other way more but losing power, then it would be effective despite not lowering BABIP, right?

And if you include other aspects of offense, which I think we can all agree that you must, what data are you using that indicates whether a shift occurred? Is there data that records shifts regardless of the outcome of the play? In other words, are shifts or no shifts recorded when a batter hits a HR or walks or strikes out?

If not, then you can NOT do a comprehensive analysis and you would have no idea whether shifts are effective or not, right, since you would have no idea how they affected walks, BB, HR, etc.?

Just wondering as I am underwhelmed by all of the shift analyses I have been reading...
There's no way to control for pitcher/park/etc. with the publicly available data. If someone has better data and can control for all of that, I am happy to read that. I used BABIP (and total bases, which is basically just SLGcon) entirely for the reason that it's the only thing available. I also strongly suspect that there is an effect on HR, BB, and K and I suspect that the effect is negative, but I can't prove it. I would love to include something more comprehensive (wOBA would be fine), but it isn't out there for me to play with.

I'm putting this all out there not fully formed because the information that we do have says something that doesn't connect with the generally accepted belief. There are plenty of ways that I could be proven wrong, and if someone can prove me wrong, then I'm wrong. I haven't the slightest bit of fear of that. I'm a married man, so it wouldn't be the first time.

There are data out there that could answer the question, but they aren't public. So, effectively, we have to sit here in partially in the dark. The only data that are available are shift splits -- based on BIS data -- that Fangraphs have put up. They only cover balls in play.

But let's take stock of what we do have on hand. We know that BABIP is at least part of the equation (and an important part at that), and for that part, the effects of the shift are quite minimal (again, in the aggregate... I don't suggest completely abandoning The Shift, but that does suggest that it's over-used). Within what restrictions we have to work with, it is at least un-settling to what had been considered a settled question, and I think that there's value in that.
I think Pizza does a good job of laying out the groundwork as well as highlighting the potholes. And that we can't come to any conclusion given the data and research publicly available.

MGL does a good job of noting all the additional variables that need to be considered, and lacking those, any conclusion is definitely too early to be stated.

I think you might be missing the author's point here though. If the shift becomes a "tell" and the pitcher changes his approach, but a power guy like Ortiz doesn't change his approach, you have effectively eliminted low and away as a pitch Ortiz needs to worry about. Instead, you have a hitter who can focus on crushing a ball in his wheelhouse. The shift is intended to get outs from strong pull hitters, but if the pitcher pitches into the shift, that might actually be playing into a guy like Ortiz's hands.

If this increases the chances that Ortiz parks one where he previously wouldn't have, that is a game changer for the shift. It means that pitching staffs, coaches, and catchers would need to reassess pitch selection and determine whether "pitching into the shift" is truly the best approach. I would argue that giving up a single on a low and away pitch to Ortiz is preferable to giving up a bomb.
No one (at least me) is missing the point. That IS my point. That pitchers and batters will clearly change their approach. Which is why we need to look at a comprehensive stat.
but if pitchers change their approach and eliminate a pitch, but a batter doesn't alter the approach to try to push the ball into the gap left by the shift, then your statement isn't accurate. if a hitter treats the shift as a tell that no low and outside pitches are coming and just keeps swinging using pill mechanics, now they have one less pitch to worry about and the pitcher is actually pitching into a pull hitter's strengths.

while the shift would still get more outs in this scenario, the shift also leads to more worst case scenarios. whether this is true is what the author is saying needs additional research. thought this was a great article.
"There are plenty of ways that I could be proven wrong, and if someone can prove me wrong, then I'm wrong."

Pizza, that's the whole point. You should NOT be drawing any conclusions about the shift "works" or not. So there should be nothing to prove you right or wrong about. You can tell us what happens to BABIP or SlgCon or whatever, but please don't draw any conclusions, even tentative or uncertain ones, about the effectiveness of shifting. Without looking at total offense there is simply NO way to draw any conclusions about the "effectiveness" of shifts. None whatsoever. Zero.

The subtitle of your article is "slightly more convincing arguments against the shift." That's complete BS. I don't know how to articulate it any better than I have. We might even EXPECT BABIP to stay the same or go up with shifts, with the assumption that batters are forced to try and go the other way more often (and thus lose power) in order to reduce the effectiveness of the shift but not eliminate it.

To be clear I have no idea or opinion on the efficacy of shifts overall or whether teams shift on too many players (e.g. they should only shift on most extreme pull hitters), but I don't think any of this BABIP data tells us anything about the overall effectiveness of shifting.

And for the record, comparing shifts and no shifts without controlling for team, pitcher, game situation, base runners, outs, parks, renders a comparison worthless in my opinion. It's not like teams are randomly shifting or not shifting so that you have a natural RCT study. There is a reason that teams shift or don't shift and those reasons likely render the two buckets unequal in terms of expected BABIP. I would never think of comparing shift and no-shift data with the assumption that will give me the EFFECT of the shift.

You say there is no way to control for pitchers, etc. Why did you say that? You have the pitchers, parks, fielders, etc. for shifts and no shifts, don't you? So tell us the collective UZR of all the fielders in both buckets, the FIP of all the pitchers, the infield park factors for all the parks in both buckets, the average base runners and outs for both buckets, etc. The platoon matchups for both buckets. That's the way to control for these things, right? How can a strict comparison of the data WITHOUT controlling for all these things, possibly be reliable when teams usually have a reason for shifting or not shifting?
Here is a perfect example of what I am talking about. Shifts, I assume, are muich more likely with GB pitchers on the mound. Don't GB pitchers allow a higher BABIP? So if the "shift" buckets is populated by more GB pitchers than the non-shift bucket, won't it appear the the shift is "causing" BABIP to go up instead of down. So, again, surely you want to tell us the G/F ratio of the pitchers in the shift versus non-shift buckets.