The infield shift is a much-maligned defensive strategy, hounded as one of the worst analytics-based changes to baseball. Multiple times each season there will be some conversation about banning the shift and each time pros, ex-players/managers, commentators and analysts will chip in with their two cents. But for now, the shift is here, and it is as popular (with the fielding teams) as it has ever been. Just under 26% of all pitches were thrown with some form of infield shift in place in 2018, 22% of at-bats had a shift for the entirety of it and 30% had at least one pitch shifted.
As you can see, left-handed hitters are far more likely to be shifted than their right-handed counterparts, with 46% of left-handed ABs seeing a shifted pitch versus 19% for righties. This makes rudimentary sense as the shifted players for a left-hander are closer to first base, so have a greater chance of impacting the play to first and therefore stopping a potential single. For more about the basic principles of the shift check my previous article here. Today we are going to take a more in-depth look to see how well they are working.
I have taken players who have 100+ at bats in 2018 both against a shifted and non-shifted infield, then compared the outcomes. There were 132 such players and their combined number of at-bats was 72,389 (39% of the seasons total). I have split these up into 4 categories based on the handedness of the batter and the pitcher.
Let’s start with the top and LHH v LHP, where we can see that that walk rate and home run rate have increased but for all other factors the shift has had a positive outcome for the pitching team. The increased walk rate is outstripped by the increased strikeout rate and the overall impact (wOBA) is down just over 6%. Shift working.
LHH v RHP. This follow a very similar pattern to the one versus LHP but with slightly higher increases to walk rate and home run rate. The positives for the pitching team are a little bit smaller as well but the overall impact is still a reduction in wOBA of 4%. Shift working.
RHH v LHP. That does not look good for the shifting teams, the only stat reduced is BABIP. More walks, less strikeouts and a higher home run rate is not what teams would be wanting off shifting these players and the overall difference is an improvement of just under 5% in wOBA. Shift not working.
RHH v RHP. As with versus LHP they walk more and strikeout less but thanks to a bigger dip in BABIP and a decreased home run rate the overall impact of the shift is a slight decrease in overall production of 1.7%. Shift just working.
So, across the board when shifted the walk rate went up, this was countered for left handed hitters by them being struck out more but not so for right handers. Now while this is interesting there are various factors which could impact these outcomes, one significant one being who the pitcher is. To remove this impact, I calculated the same rates for all pitchers in 2018 and pro rata’d them to give expected rates from these at bats. Using those figures, I then calculated how much above or below this expected outcome the results were. I scaled this to 100, with 100 being inline, less than 100 being below average and greater than 100 being above average.
As before you can still see the same patterns in the difference between shifted and non-shifted at-bats. The percentages have changed but most not significantly. This still shows that shifting is overall (wOBA) working against left handed hitters and isn’t against right handed hitters when they face left handed pitchers.
How a team shifts and where they position their infielders can be affected by the number of runners on base. To truly interpret if these changes are the impact of the shift, we should look at cases where the bases are empty. The table below does so, with the same logic of comparing it to pitcher averages.
Accounting for bases empty scenarios only we now see that shifting isn’t working at all against right-handers. It is reducing BABIP but with increases in walks and home run rate, and decreases in strikeout rate, the overall impact on batter performance is an increase and not the expected decrease. Left handers remain the same as before with the impact more significant for left v left encounters. Also, this now shows that in all scenarios the home run rate is higher when shifted.
What is going on when teams are shifting right handers? I investigated the pitches thrown at right handers and there were some small differences.
RHH v LHP – Fastball rate (2 & 4 Seam) dropped from 43.7% with no shift to 40.5% with a shift and sinker usage dropped from 10.4% to 8.9%. Change ups, cutters and sliders all had increased throwing percentages of 1-2%.
RHH v RHP – Fastball rate (2 & 4 Seam) increased from 46.4% to 48.8% when shifted and sinker usage dropped from 2.3%. All other pitches didn’t change by more than 1%.
With these differences being opposite, bar the sinker usage, it doesn’t show anything jumping out as being the reason behind the difference. I decided to look at the hitters instead to see if they showed any difference in approach when being shifted and there were a few interesting things to be found.
The RHHs with the most shifted at bats (empty bases only) were Brian Dozier, Rhys Hoskins and Andrew McCutchen. When facing RHPs Dozier slightly improved his K-BB rate but drastically increased his HR/Contact% going from 1.5% on non-shifted AB (101) to 10% on shifted AB (151).
When facing RHP Hoskins’ strikeout rate drops from 26% to 14% when facing a shift (134 AB for shift and no-shift), his BABIP is .347 up from .235 and his wOBA is .472 compared to .363. His expected stats are also better when shifted with xwOBA .100 better showing this difference isn’t down to the luck of a better BABIP. McCutchen walked more and struck out less when shifted but had a HR/Contact% of 0% against LHP in 75 shifted AB and a rate of 9.2% against RHP in 121 shifted AB.
Looking at the data for these 3 players it reads as a very compelling case for them not to be shifted. But it isn’t just those three which paint a bad picture for shifting right handers. Also, in the top 10 for most shifted is J.D. Martinez and Mike Trout. These are two of the best hitters in the league and I don’t know if teams are looking to do this just to try something different or not because these two are just unstoppable. Versus RHP under the shift Martinez walks more and strikes out less moving his wOBA up to .440 compared to .420 against non-shift. Trout’s BABIP drops from .370 to .265 under the shift against RHP but like many others his walk rate is higher, his strikeout rate is lower and his HR/Contact rate goes up to 14% from 10%. All that combined means that Trout’s wOBA is 0.443 against the shift compared to 0.445 without.
Finally, I want to highlight the stats for Evan Longoria. He had 131 non-shifted at bats against RHP, he didn’t draw a walk once! He had a strikeout rate, and a K-BB%, of 24.4%. When shifted he improved his K-BB% to 7.1% and improved his wOBA to .349 up from .324. This looks like such a premeditated approach from Longoria.
These are all sample sizes which are too small to extrapolate with much meaning but there does seem to be a change in the approach for some of these batters when they are shifted. They are walking more, striking out less and hitting more home runs. It looks like they are being more cautious when they are being shifted and in doing so these batters are reaping the benefits.
By looking beyond the impact to BABIP it looks clear to me that the shift against right handers is not working. Now I haven’t worked out if certain teams are getting it right while others are getting it wrong, but before MLB bans the shift they may want to look into it further as it is making some batters better…
Featured Image Photo Credit : MLB