CSS Button No Image Css3Menu.com

Baseball Prospectus home
  
  
Click here to log in Click here for forgotten password Click here to subscribe

Happy Labor Day Weekend! Regularly Scheduled Articles Will Resume Tuesday, September 8

<< Previous Article
Premium Article Moonshot: Survival of ... (07/01)
<< Previous Column
Premium Article Baseball Therapy: Is i... (06/24)
Next Column >>
Premium Article Baseball Therapy: What... (07/08)
Next Article >>
Premium Article Overthinking It: The N... (07/01)

July 1, 2014

Baseball Therapy

Do Some Pitches Do More Damage Than Others?

by Russell A. Carleton

the archives are now free.

All Baseball Prospectus Premium and Fantasy articles more than a year old are now free as a thank you to the entire Internet for making our work possible.

Not a subscriber? Get exclusive content like this delivered hot to your inbox every weekday. Click here for more information on Baseball Prospectus subscriptions or use the buttons to the right to subscribe and get instant access to the best baseball content on the web.

Subscribe for $4.95 per month
Recurring subscription - cancel anytime.


a 33% savings over the monthly price!

Purchase a $39.95 gift subscription
a 33% savings over the monthly price!

Already a subscriber? Click here and use the blue login bar to log in.

In their recent “position paper” on preventing elbow injuries in Major League (and Minor League and College and High School and Little League) Baseball, Drs. James Andrews and Glen Fleisig had an interesting recommendation for young pitchers: Don’t throw with 100 percent effort on every pitch. The arm, particularly the elbow, isn’t made to take that much stress all the time.

In a recent article at the site RotoScouting, Ben Flajole picked up the idea from a more pragmatic point of view. He looked at the case of Jose Fernandez of the Marlins, who was recently shelved by Tommy John surgery. Last year, Fernandez played on a Marlins team that, outside of Giancarlo Stanton, was, shall we say, offensively challenged. Despite his heroics, he was pitching either behind in the score or with only a small lead more often than the average bear. On another team, he might have had the luxury of throwing more innings in which he was ahead 7-2, and where he wouldn’t have had to worry as much. (Even if he gives up a leadoff home run in the inning, it’s only 7-3.) Flajole suggests that because Fernandez was often pitching with the game “on the line” he might have over-extended himself a bit and pitched at max effort more of the time than most, and that that could have contributed to his eventual demise.

I know that there are already some people snickering at the idea of pitchers “pitching to the score,” but the idea at least passes the silly test. Pitchers might view some hitters or situations as more important and might alter their arm action accordingly. Whether or not that’s a logically sound strategy to follow is irrelevant. Humans aren’t logical creatures and pitchers are human. Whadayasay we take a look?

Warning! Gory Mathematical Details Ahead!
First we need to figure out what we’re looking for. Flajole’s article suggests that “solo home run situations” or situations in which the game is either tied or within one run (either way) are the ones to look at. I also looked at situations in which the pitcher was literally one pitch away from surrendering either a tie or a lead. If the pitcher’s team was tied or ahead, but a home run by the batter at the plate would have either tied the game or put the batting team ahead, I counted it. We don’t know from pitcher to pitcher whether he’s reaching back for a little extra from pitch to pitch, but if there’s signal in there, this should at least let us see it a bit.

I counted the number of pitches that pitchers threw in these types of situations over the course of a year. Then, as I did in a few other articles on pitcher injuries that I’ve previously written, I looked at starting pitcher injuries from 2002-2012. In the past, I’ve found that two very powerful (and very non-surprising) predictors of a pitcher’s injury risk for the upcoming year are his prior injury history, particularly an injury history to a specific body part (i.e., elbow injuries predict elbow injuries, but not necessarily shoulder injuries) and his overall pitch count from the year before.

To keep the model nice and neat, I ran a logistic regression predicting whether or not a starter would end up with a shoulder injury based on four factors: a shoulder injury last year, a shoulder injury two years ago, his total pitch count from last year, and the number of pitches thrown in these “solo homerun situations.” I did the same for elbow injuries.

The results: As expected, previous injury history entered the regression first (for the initiated, I ran it stepwise) indicating that it was the most powerful predictor. However, the pitch count from situations where a homerun could tie the game or put a team into the lead was next, before the overall pitch count entered, at least for shoulder injuries. The number of high-stress pitches last year is a better indicator of shoulder injury than the total number of pitches. It was not a predictor (nor was overall pitch count) for elbow injuries. When I defined high-stress pitch counts as those coming during times when the game was within a run or tied, that didn’t predict anything.

Reaching Back for an Injury?
In key situations, pitchers often “reach back for a little more.” Is it possible that while they’re reaching back there, they’re grabbing an injury? The evidence here isn’t very compelling. Changing the definition of “key situation” makes the findings change. Usually, that’s a sign that the effect isn’t very robust.

This could be a case where the aggregate results don’t do the individual effects justice. For example, in the article on Jose Fernandez, Mr. Flajole suggests that when Jose Fernandez reached a two-strike count, he increased his use of breaking pitches more than a pitcher usually does with two strikes. Maybe some pitchers, when faced with a lot of close situations, default to riskier pitch selections or throw at 100 percent effort more than they should. The fact that Fernandez pitched in a lot of close situations combined with this own habits may really have been what hurt his elbow. Mathematically, we would say that the two factors interact with one another to create a moderator effect. Once again, the simple model probably isn’t sensitive enough to get at what we want to see.

It’s not that the hypothesis that a player’s circumstances might affect his injury chances is necessarily false. It’s that the variables that drive those injuries are related to each other in ways that are complex, both conceptually and mathematically. The tough part is that the combinations of factors that we’re looking at might not occur in big enough numbers to provide the sample size to power the sorts of research designs that would be helpful in figuring this all out. But I’d argue that Mr. Flajole’s argument points to a reasonable question. If Jose Fernandez had been pitching for a team where he didn’t always feel that he was “pitching with the game on the line,” would he still be pitching today? Right now, we don’t know the answer to that question, but it’s not a silly one to ask.

Russell A. Carleton is an author of Baseball Prospectus. 
Click here to see Russell's other articles. You can contact Russell by clicking here

Related Content:  Pitchers,  Injuries

4 comments have been left for this article.

<< Previous Article
Premium Article Moonshot: Survival of ... (07/01)
<< Previous Column
Premium Article Baseball Therapy: Is i... (06/24)
Next Column >>
Premium Article Baseball Therapy: What... (07/08)
Next Article >>
Premium Article Overthinking It: The N... (07/01)

RECENTLY AT BASEBALL PROSPECTUS
Fantasy Rounders: Miggy's the Bouncer
Premium Article The Prospectus Hit List: September 4, 2015
Premium Article Prospect Profile: Kevin Newman
Premium Article Minor League Update: Games of September 3, 2...
Premium Article Transaction Analysis: All Outfielders Go to ...
Premium Article The Call-Up: Corey Seager
Premium Article Pitching Backward: On Manager Analysis

MORE FROM JULY 1, 2014
Premium Article Moonshot: Survival of the Fittest: Pitchers
Premium Article What You Need to Know: Davis Downs the A's
Premium Article Minor League Update: Games of Monday, June 3...
Fantasy Article The Buyer's Guide: Jake Arrieta
Fantasy Article The Stash List: 12th Edition
Fantasy Article Deep Impact: Week 13
Daily League Strategy: Leake and Locke

MORE BY RUSSELL A. CARLETON
2014-07-08 - Premium Article Baseball Therapy: What is a Fast Runner Wort...
2014-07-04 - BP Daily Podcast: Effectively Wild Episode 4...
2014-07-03 - BP Daily Podcast: Effectively Wild Episode 4...
2014-07-01 - Premium Article Baseball Therapy: Do Some Pitches Do More Da...
2014-06-24 - Premium Article Baseball Therapy: Is it Really Harder to Sco...
2014-06-19 - Baseball Therapy: Should You Trust the Proje...
2014-06-17 - Baseball Therapy: What High School Has to Do...
More...

MORE BASEBALL THERAPY
2014-07-29 - Premium Article Baseball Therapy: Trading Ryan Howard For No...
2014-07-15 - Premium Article Baseball Therapy: Why Are We Playing Hunger ...
2014-07-08 - Premium Article Baseball Therapy: What is a Fast Runner Wort...
2014-07-01 - Premium Article Baseball Therapy: Do Some Pitches Do More Da...
2014-06-24 - Premium Article Baseball Therapy: Is it Really Harder to Sco...
2014-06-19 - Baseball Therapy: Should You Trust the Proje...
2014-06-17 - Baseball Therapy: What High School Has to Do...
More...