In 2017 the number of defensive shifts in the MLB decreased year on year for the first time since 2011, but to put that in context back in 2011 they were still only accounting for less than 2% of all at bats where as in 2017 it was 18%. From the 2010 season to 2016 the number of defensive shifts had increased by a factor of over 10 from 3,323 at bats in 2010 to 34,801 in 2016. Each of the 5 seasons before 2017 had seen at least a 35% increase in shifts year on year so 2017 was neigh on certain to a record number once again. But as Benjamin Franklin once said ‘In this world nothing can be said to be certain, except death and taxes.’
Lets take a quick step back though, a shift is a term used to describe the situational defensive realignment of fielders away from their “traditional” starting points. The MLB site has great piece here on the different type of shifts and all data on shifts used in this article has been collated from fangraphs data, grouping all the different types of shifts together.
Standard Infield Shift Strategic Infield Shift
Infield shifts were originally designed to protect against base hits pulled hard into the gaps between the fielders on the right side when a left hander hit and they have been around a lot longer than you might think. There is record use of them in the 1920s and one was used on Ted Williams during the 1946 World Series by St Louis, but back then it was considered more of a physiological move and not tactical like the shifts we have in modern baseball.
So, the first question is why did the trend get bucked and the shift percentage dropped in 2017? And the second question was this down to certain teams or the same across all the teams?
I decided to look at two statistics to determine shifts overall effectiveness to see if that was the reason for the drop in usage. BABIP (batting average on balls in play) and wOBA (weight on-base average). BABIP measures how often a ball in play goes for a hit. A ball is “in play” when the plate appearance ends in something other than a strikeout, walk, hit batter, catcher’s interference, sacrifice bunt, or home run. wOBA is based on a simple concept: Not all hits are created equal and that slugging percentage weighs extra base hits too high. It combines all the different aspects of hitting into one metric, weighting each of them in proportion to their actual run value.
If a defensive shift is dong its job right you would expect the BABIP for shifted at bats to be lower, more groundouts to the shifted infield players or flyouts to the shifted outfield players, and you would also expect the wOBA to be down as well for the same reason. I compared the data for LHH (Left Hand Hitters) and RHH (Right Handed Hitters) differently as lefties get shifted far more than right handers. The reason for this difference is due to it being easier for an infielder shifted into shallow right field to get the pulled ball, by a lefty, to first for the ground out than is for one shifted into left field for a pull from a righty.
As you can see from this high level analysis, for left handed hitters the BABIP is lower when there has been a shift for every year except 2010 and 2016. For right handers the data is a little more erratic due to the low number of shifts that occurred in the early years of the decade but it also shows that for 2016 the difference for the shift was minimal compared to the years around it. So the data shows no major difference in BABIP for 2016. This could be behind why we saw less in shifts 2017, a reaction to what happened in 2016, but lets look at the wOBA.
Now these wOBA graphs show a greater decrease for the shift compared to the league average, the same erratic data is their for right handers earlier on. But to me this would suggest that shifting on the whole is working but there were some potential alarm calls in 2016. So let look closer at some teams to see if we can see anything more specific.
There were 20 teams which had a decrease in shift usage last season and there were 4 teams which had a decrease of over 25%. These were the Atlanta Braves (26%), Los Angeles Angels (28%), Colorado Rockies (42%) and St Louis Cardinals (48%). Three of these had an increase in shift usage of over 100% in 2016 and other team, the Rockies, had an increase of 550% in 2015, so these teams were all relatively late adopters of the defensive shift but the by end of 2016 they all ranked in the top 12 for most shifts.
Looking at the Braves in further detail their BABIP and wOBA figures show no reason why they should have shifted less as it was working for them, in line with league figures. The only reason I can see why they changed was they had a change of GM and he didn’t want to implement it as much. I won’t be able to know if that is truly the case or not as John Coppolella isn’t the Braves GM anymore and is banned for life from baseball (that is an entirely different story).
The Angels number did show a slightly elevated BABIP, higher for LHH shifts than non shifts, for 2016 which may been responsible for the drop in shifting they did. For 2017 they dropped the shift numbers and their figures ended up being more inline with the rest of the MLB with BABIP and wOBA lower for shifts and looked much better than the previous 2 years.
The Rockies BABIP and wOBA showed no reason to change to be perfectly honest, their numbers were better than league average. No managerial change took place either, the infield personal were largely unchanged as well with only the addition of 1B Ian Desmond and a first baseman should have little impact on a teams shifting ability.
On the other hand it looks like the Cardinals were getting it wrong, their BABIP was up 7% for shifts compared to non shifts and wOBA nearly in line, closest to the non shift line for any team. Sadly the Fangraphs data doesn’t got into the detail where I can see who they were shifting to see if they were shifting against the wrong batters or if they were worse at shifting than other teams. So it seems they cut back in 2017 as they were getting it wrong in 2016 and like the Angels their figures for 2017 were much more respectable when they cut back on the shifts.
So 2017 saw some drops but also saw some big adopters the White Sox and the Marlins had increased shift usage of 50+%, these two team were ranked the highest they had ever been in the team shift rankings in 2017. For most of the teams there figures were in line with the previous year (13 in +/- 10%) this data seems suggest they were happy with what they were doing and not looking to expand it.
Another, probably superfluous, factor that could have affected the shift numbers was the World Series Winners, in 2016 the Cubs won with the lowest number of shifts of any team. So maybe clubs wanted to follow them as they showed it wasn’t required to be the best. But in 2017 the Astros won with the most shifts so who knows what is actually best for the teams.
The shift died slightly in 2017. So, what about this season so far? All the stats show 2018 is back in line to be a record year. There are 7 teams with an increase shift rate of 50% on 2017 including 3 of the 4 with big drop teams last year, it looks like teams honed in the skill last year and are expanding it out again. On top of that we have the Kansas City Royals that are going at it hard, they have jumped to 3rd in 2018 from 24th in the 2017 for teams with most shifts. Their GM was saying preseason that they were going all in and it certainly looks the case.
So, am I certain that the number of shifts will be new record by the end of the 2018, no I am not but looks like the growth is alive once again. So if you are you are Chris Davis or Joey Gallo you can continue to expect to be shifted 90% of the time and if you are left handed hitter and you develop the propensity to pull the ball you will get shifted more. If you are everyone else in MLB you should expect to be shifted more and more because each team is getting loads more data about it and it is looking like it works.