You should be accustomed to seeing something like this from me by now, but here’s a quick primer. In the upper-left we have total pitches thrown from each type of pitcher to each batter. All data comes from Brooks Baseball and I have left out the knuckle ball and intentional balls. Breaking balls (BB) are comprised of curves, sliders, and knuckle curves while change ups (CH) are defined as change ups and split finger fastballs. Lastly, fastballs (FA) are made up of two-seamers, four-seamers, cutters, sinkers, and screwballs.
Working our way down to the lower-left quadrant I have turned the raw number of pitches into a percentage from each type of pitcher. The total column shows the number of pitches thrown by that type of pitcher so Ben Zobrist saw 32% of all his pitches from lefties and so on.
In the upper-right we use Run Values as calculated by Harry Pavlidis (I would link but their site is down at the moment). These adjust for count and are the best reference I’ve found for this sort of thing. In the bottom right we take the raw Run Values and adjust them to be per 100 pitches to get an idea of what the rate looks like compared to the total value.
Use this as a cheat sheet and please let me know of any questions in the comments. I’d love to delve into this stuff more thoroughly, but I think you, the reader, are capable to picking through this and I’m excited to roll out the individual stuff. I will be showing each one of these batters, but I want to space it out since you’re going to see a lot of stuff.
We’ll start with Ben Zobrist and work alphabetically off of first names from here on out. Let’s start by revisiting some of what we’ve already seen above, but augmenting with zone and strike data. The zone data is based off of the fantastic work by John Walsh:
Z% is the percent of pitches in the zone and the same for S% except looking at swings. Against lefties Zobrist had positive run values against the breaking ball, but that is it. He laid off the breaking ball more than other pitches and with good reason as these caught the zone at a much lower rate. He really seemed to struggle with the change up as he swung at as many changes as he did fastballs with the former being in the zone much less often. As an aside, I think comparing zone and swing rates could be a positive externality of this research as this could lead to a better understanding of patience versus passivity. Some other time, perhaps.
He was much better against righties where all pitches had positive run values, though the fastball just squeaked in there. Pitches pounded the zone a little bit more, for the most part, but Zobrist showed even more patience against northpaws swinging only 39% of the time while seeing 58% of all pitches in the zone. He feasted on the change up and was no slouch against the bendy stuff, too.
Now I want to move into what I’m really excited about. I think the following charts can give a solid overhead view of when a batter is struggling and whether they were able to make an adjustment or not. This should give a level of understanding of consistency, but also how well a batter was able to perform day in and day out. Let’s start with breaking balls from lefties:
Learn the format, because it’s going to be used extensively throughout this series. These are 50-pitch moving averages for Zone and Swing rates and Run Values. On the primary axis (on the left) we have percentages for zone and swing rates throughout the season to gauge how often pitchers were throwing strikes and how batters protected that zone. On the secondary axis (on the right) we have Run Values to approximate performance. Unlike traditional metrics that only look at the outcome of the at bat, we get a much better understanding of how the batter performed because we’re not looking at only the pitch that ended the at bat, but everything in between. Remember that positive values indicate good and negative not so good so use that gridline at 0 as your gauge of performance.
A quick rundown since this is the first time I’m showing this. Early in the season lefties were throwing the breaking ball in the zone a ton with Zobrist not swinging all that often. He mostly swung around the same rate over the first 100 or so pitches, while pitchers continued to offer less and less in the zone. As pitchers started to settle in between 40 and 50% Ben was swinging between 30 and 40% of the time and his second half shows solid run values indicating good decisions and results. Let’s move on to change ups from lefties:
Ben was below average against the lefty change until late in the season when he started to see moderate success. This didn’t really happen until pitchers stopped throwing the offspeed pitch for strikes so often and he was swinging about as often as they were willing to throw it in the zone. This should not be read as that he was only swinging at strikes, but I think good things happen when your swing and zone rates are pretty closely aligned. This is the game theory of batting. If a batter’s swing rate is very low there is no reason for a pitcher to not throw strikes and vice-versa, but we see how both sides are seeking the optimum which incentivizes them to approximate each other’s rates. How about the fastball:
With the fastball we have a much larger sample size to look at here compared to the secondary stuff which gives us a great notion as to how these things interplay. As a patient hitter Ben is usually going to see a higher zone rate than swing rate and that played out for the most part here except for that one spike in his swing rate between 200 and 300 pitches when he swung about as often as pitchers threw him a strike. Correlation does not equal causation, but it’s interesting that some of his lowest run values on the fastball occurred when he was becoming more of a free swinger. There were spurts of extended productivity, but it was not the norm. Let’s move on to breaking balls from righties:
The righthander’s breaking ball saw Ben’s second best performance per 100 pitches and you can readily see the gap between zone and swing rates here. He laid off the pitch throughout the season with a couple of spikes showing that he was willing to offer a bit more at times to keep pitchers honest. His performance really peaked in the middle of the season, but even then you’ll notice a couple of dips below the average. Here’s a look at change ups:
Ben showed incredible success against the righty change, but you can see that he did start to fall off from his high standards during the last quarter of the year. Finally, let’s move on to fastballs:
We can still see the gap here between strikes and swings and it looks like when things were going well they were really going well with his peaks being well above the average, but for the most part he was oscillating around the norm. The last strong peak is interesting that you see his swing rate so low, but so was the strike rate and as pitchers threw more strikes he amped up his swings to close out the year.
Ben turns out to be a good person to start this series out on because of his patient nature and the fact that he’s a pretty good hitter, for the most part, overall. He uncharacteristically struggled some against lefties this past year despite showing a little less of his patented approach, but this does a nice job of showing that even his weaknesses show some strength over short runs. I hope you enjoy this stuff, because there’s a lot more to look forward to over the coming weeks.