In part 1 of this series, a macro level attempt was made to understand what causes the Time Through the Order Penalty (TTOP). While there was some interesting information uncovered in part 1, taking a more individual player focused approach in this part will likely yield better results.
Most baseball followers are likely familiar with the idea that pitchers typically lose effectiveness the second and third time they face an opposing lineup. While taking a macro-level look at this problem in part 1 of this series, I was unable to uncover any particular evidence that would point to pitch quality decreasing each Time Through the Order (TTO), certain information uncovered however showed a noticeable change in hitters approaches at the plate. In 2019 hitters swung much more frequently the more times they faced an opposing pitcher. Taking a more individualized approach in this part while hopefully yielding better results on the pitch quality/command side of things.
It was theorized in part 1 of this series that better starters overall were going to most frequently get the opportunity to face an opposing lineup a third time through. By looking at the 10 starting pitchers in 2019 with the most pitches thrown the third time facing an opposing lineup, we can see that 6 of these starters are also ranked among the top-10 in starting pitchers fWAR leaders at Fangraphs. For the sake of time, only the following starters will be considered and each of these pitchers gives us a fairly large sample of pitches to work with each TTO.
Trevor Bauer 2019 TTO Statistics
In terms of ERA and wOBA, Trevor Bauer got worse each of the times he faced an opposing lineup in 2019. To begin to understand some potential causes of this one can use Bauer’s statcast pitch-by-pitch data from 2019. To start, we can break each of his pitches down by TTO and xwOBA.
Trevor Bauer 2019 xwOBA by Pitch and TTO
|TTO||Four-Seam xwOBA||Cutter xwOBA||Curveball xwOBA||Slider xwOBA|
Despite Bauer’s ERA and wOBA getting worse each TTO, most of his pitches actually did better in terms of xwOBA the second time facing an opposing lineup in 2019. We can further begin to understand some potential causes of this by looking at a velocity density plot (with the density representing total number of pitches) for each separate time through the order faceted by each pitch type.
Bauer did well maintaining his velocity throughout the course of his starts in 2019 and a number of his pitches even saw their average velocity increase each of the times through the order. It certainly doesn’t appear velocity caused his diminished performance as his starts progressed last year. There are certainly other factors that must be considered on the pitch quality side of things however.
In part 1 of this series league average spin rates were displayed for each pitch type and TTO. While looking at the league average spin rates didn’t uncover much, it will likely be a little better looking at individual pitchers. By looking at Bauer’s data from 2019, we can graph the average spin rate for each of his most frequently used pitches for each separate TTO.
It appears the average spin rate for all of Bauer’s pitches increased the second TTO before all of them decreased his third time facing an opposing lineup. As we previously saw, the xwOBA against most of Bauer’s pitches decreased the second time facing an opposing, before ultimately falling off the third time facing an opposing lineup. While active spin is the amount of spin that contributes to movement, raw spin can also begin to help us understand a pitches movement profile.
In part 1, an attempt was made to understand how well pitchers did locating their pitches each of the separate times through the order. By looking at what Baseball Savant calls attack zones (see below) it was determined that pitchers were working less frequently in the heart region and more in the shadow, chase and waste zones as a start progresses. As previously mentioned, it was also determined in part 1 that hitters will swing much more frequently the more times they face an opposing pitcher. This fact in particular makes it much more important for pitchers to avoid working in the heart region of the plate as a start progresses. It is mostly going to be optimal for pitchers to work in the shadow region of the zone and more than 42% of all Major League pitches were located in this region in 2019.
2019 Trevor Bauer Attack Zones % by TTO
While Bauer was better locating pitches in the shadow zone the second time facing an opposing order in 2019, he located pitches in this zone at a much lower rate facing an opposing lineup a third time through. Perhaps him working in the shadow region at an increased rate the second TTO explains why the xwOBA against many of his pitches actually improved his second time facing an opposing lineup. It should also be considered that he locates fewer pitches in the heart zone and more in the chase and waste zones as his starts progress. This is certainly interesting, but before jumping to conclusions other pitchers must be considered.
Stephen Strasburg 2019 TTO Statistics
Strasburg looks different from Bauer in the fact that his ERA and wOBA actually improved the third time he faced an opposing lineup in 2019. Like we did for Bauer, we can break down each of his most frequently thrown pitches from 2019 by xwOBA and TTO.
Strasburg 2019 xwOBA by Pitch and TTO
|TT0||Four-Seam xwOBA||Two-Seam xwOBA||Change-Up xwOBA||Curveball xwOBA|
Despite the results against some of his pitches getting much worse the second time he faced an opposing lineup in 2019, some of Strasburg’s pitches were able to get much better results the third time he faced an opposing lineup. In an attempt to determine if some aspect of pitch quality is perhaps causing this, we can look into his Statcast pitch-by-pitch data from 2019.
While the average velocity on all of the above pitches decreased slightly his second time facing an opposing lineup in 2019, he was able to maintain the average velocity on each pitch type his third time facing the opposing order. While this is certainly noteworthy, the slight decrease in average velocity on it’s own likely isn’t enough to explain why he got so much worse facing an opposing lineup a second time through. There are certainly other potential factors to consider.
It doesn’t appear that Strasburg’s spin rates are significantly affected the further he gets into a start. In an attempt to further understand what causes him to get much worse his second time facing an opposing order we can look at his attack zone percentages broken down by TTO.
2019 Stephen Strasburg Attack Zones % by TTO
Strasburg started working more in the heart region and less in the shadow region his second TTO in 2019. It is already been mentioned how batters swing more frequently as a start progresses and thus it is even more important for pitchers to avoid working in the heart region of the strike zone as a start progresses. Strasburg working more in the heart and less in the shadow region his second TTO and then subsequently working less in the heart and more in the shadow region his third TTO in 2019 might begin to provide a good explanation for the fluctuations seen in his overall numbers each of these times through the order.
To further examine if pitcher command can be identified as a potential explanation for the times through the order penalty, let us consider another pitcher.
Gerrit Cole 2019 TTO Statistics
Cole got better his second time facing an opposing lineup before ultimately getting worse his third time facing an opposing lineup in 2019. Like with the others, we can begin to look into what might be causing this by breaking down his pitches by xwOBA and TTO.
2019 Gerrit Cole xwOBA by Pitch Type and TTO
|TTO||Four-Seam xwOBA||Slider xwOBA||Curveball xwOBA||Change-Up xwOBA|
It looks like while most his pitches got better his second time facing an opposing lineup, his curveball got much worse the second TTO before improving again his third TTO (Change-up was thrown for less than 10% of total pitches). Like the others, we can break down Cole’s velocity by pitch type and TTO to see if there are any noticeable trends as his starts progress.
Cole is another pitcher who did pretty good maintaining his velocity throughout his starts in 2019 and his average velocity actually increased for some of his pitches as his starts progressed last year. While velocity certainly doesn’t appear to be a factor here, let’s consider Cole’s spin rates.
Cole also was able to increase the spin rates on most of his pitches the more times he faced an opposing lineup in 2019. Since it certainly doesn’t appear Cole’s stuff was the reason behind him getting worse the second time facing an opposing lineup last year, let’s check out how he did locating his pitches each TTO.
2019 Gerrit Cole Attack Zones % by TTO
We can see that Cole starts working less in the heart zone and more in the shadow zone as a start progresses. While there are certainly other factors potentially at play, it is likely not a coincidence that the pitchers highlighted who maintained or even improved the rates at which they are able to work in the shadow region as a start progresses were also the pitchers whose performance don’t get significantly worse the third TTO.
While many others have attempted to understand the potential causes of the TTOP, there are certain significant factors that may have been overlooked. From the pitchers considered, it certainly looks like there is evidence that shows pitch location might play a big part in decreased pitcher effectiveness as starts progress. No matter the quality of ones arsenal, it is oftentimes the ability of a pitcher to consistently locate his pitches that goes a long ways to determine how successful he will be.
All statistics and data courtesy of fangraphs.com and Baseball Savant.com