So far this off-season, we have learned that five different relievers may be transitioning to the starting rotation in 2012: Neftali Feliz, Aaron Crow, Jim Johnson, Daniel Bard, and Jeff Samardzija. Some shudder at the thought of a pitcher being handed a much larger workload after working as a reliever for a few seasons, while some simply step back and point at C.J. Wilson who has thrown back-to-back 200+ inning seasons after working as a reliever from 2006-2010.
Instant access to athletes is one of the great things about Twitter, but it is even better when those athletes respond to people, and Wilson’s account (@str8edgeracer) is one of the best player accounts to follow. I had asked him a question in 2010 about when he started to ready himself to work as a starting pitcher, and he replied that it was within a few days following the conclusion of the 2009 season. None of the pitchers on our list, however, were given that much notice to begin working their body to prepare for the increased workload, and some are still iffy as to whether they’ll make the transition at all.
We are fortunate enough to have a large body of work here on Pitcher Abuse Points throughout the years as well as the work on the Injury Nexus by Will Carroll and Nate Silver, but I feel an update as to how workload increases affect pitchers the season in which their workload increases is worth a visit with at least four of the five pitchers mentioned in the first paragraph rather valuable fantasy draft day targets in either capacity as a pitcher.
Our wonderful stats team pulled a report showing instances of a pitcher throwing at least 750 more pitches than the season before and found 1112 instances of pitchers that qualified since 1988, which was the first season that full pitch count data was available on the pull. As a whole, there was an average of 865 pitches thrown in the base season with 2205 thrown in the following season—an increase of 61 percent. The breakdown of the metrics for each season are represented in the table below.
SEASON |
PITCHES |
K/9 |
BB/9 |
HR/9 |
FIP |
|
Year 1 |
865 |
7.0 |
3.6 |
0.9 |
3.53 |
4.19 |
Year 2 |
2205 |
6.6 |
3.4 |
1.0 |
4.19 |
4.20 |
Difference |
1340 |
-0.5 |
-0.1 |
0.1 |
0.65 |
0.01 |
While ERA did not suffer, FIP certainly did, and there was a drop-off in strikeout rates for the group as a whole. The initial data pull request also required all pitchers to be under the age of 30, but given the age differences of the four pitchers introduced in the first paragraph, it would be wise to break down the group into more specific age groups to see how the overall numbers are affected.
The following table shows 524 instances of pitchers under the age of 25 who had workload increases of at least 750 pitches from one season to the next:
SEASON |
PITCHES |
K/9 |
BB/9 |
HR/9 |
||
Year 1 |
864 |
7.4 |
3.5 |
0.8 |
3.24 |
4.07 |
Year 2 |
2251 |
6.8 |
3.6 |
1.0 |
4.17 |
4.25 |
Difference |
1386 |
-0.6 |
0.1 |
0.2 |
0.93 |
0.1 |
This next table shows 588 instances of pitchers 25 to 29 years old who had workload increases of at least 750 pitches from one season to the next:
SEASON |
PITCHES |
K/9 |
BB/9 |
HR/9 |
||
Year 1 |
864 |
6.7 |
3.6 |
0.9 |
3.81 |
4.30 |
Year 2 |
2165 |
6.5 |
3.3 |
1.0 |
4.20 |
4.15 |
Difference |
1301 |
-0.2 |
-0.3 |
0.1 |
0.39 |
-0.15 |
The younger group of pitchers showed more volatility to their performance than the slightly more experienced pitchers, which is normally expected of pitchers their first few seasons in a league as they are in a steeper part of the age curve. If we focus the numbers on the instances of pitchers working in the aforementioned injury nexus ages of 23 and younger, the data changes again:
SEASON |
PITCHES |
K/9 |
BB/9 |
HR/9 |
||
Year 1 |
844 |
7.6 |
3.5 |
0.8 |
3.21 |
3.96 |
Year 2 |
2237 |
6.8 |
3.7 |
1.0 |
4.18 |
4.25 |
Difference |
1393 |
-0.8 |
0.2 |
0.2 |
0.97 |
0.29 |
This shows that most of the volatility with the younger half of the sample size comes from its own younger half.
We don’t know how the changing of roles will affect Bard, Crow, Feliz, Johnson, or Samardzija in 2012, but the data shows that there is some kind of skills drop-off the following season when examining the pitchers that have done what they’re embarking on this season. In a dynasty league, this bares closer scrutiny as you make a decision to extend or jettison these pitchers via a terminating contract or even a trade within the season. There can be an example such as Brandon Beachy who saw his workload spike 755 pitches from his work in 2010 to the majors in 2011 but saw an increase in his K/9 by 3.2 or a Chad Billingsley who absorbed the extra workload in 2007 to be more dominant than he was in 2006. Conversely, a Tim Redding can happen where a K/9 rate goes from 9.1 to 5.9 the next season.
Thank you for reading
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Pitchers under age 25 who increase workload by more than 30 IP suffer significant injury or performace decline the next yr. It is amazingly accurate for the typically 4-6 pitchers that qualify each yr. It is one of the main reasons team have been using IP Caps last few yrs.
However, you would have to approach Yr 3 somewhat different than pitch count only because many of these pitcher miss time due to injury.