2013 Starting Pitching DL Projections.
One pitcher trait which is consistently desired through all the various fantasy formats is health. While hitters get hurt also, pitcher injuries can really put a damper on a fantasy team because pitchers are lost for longer periods of time. By knowing which pitchers are more at risk can help a fantasy owner make better decisions on draft/auction day.
A couple of years ago, I created a formula to predict the chance a player will go on the DL. On average, a starting pitcher who has thrown at least 120 innings the previous season will have a 39% chance of going on the disabled list (DL) at some point during the next season.
After its first season being put to the test, the predictions held up. Before last season, I put the formula again to the test and the results were just as encouraging. Of the 20 pitchers least likely to go on the DL, only 5 (or 25%) of them did. The model predicted 6.1 would head to the DL. On the other hand, of the 20 most likely to go on the DL, the model predicted 10.2 to go to the DL with 10 of the injury risk pitchers making the trip. The model stood up pretty good.
I have run the model again. Here are the top five most and least likely pitchers to see the DL In 2013:
| Name | DL Chance |
| Clayton Kershaw | 28.1% |
| Trevor Cahill | 28.3% |
| Madison Bumgarner | 28.3% |
| Rick Porcello | 28.8% |
| Felix Hernandez | 30.0% |
| ….. | … |
| Cliff Lee | 51.1% |
| Joe Blanton | 51.9% |
| Aaron Harang | 52.2% |
| Kevin Millwood | 52.8% |
| Bartolo Colon | 61.2% |
Besides the general DL chances, I found 2 groups of pitchers who are more likely to be injury prone. The first is pitchers who throw a large percentage of breaking balls. I found pitchers who threw sliders 30% of the time ended up on the DL 46% of the time. For pitchers who threw curve balls 25% of the time, they end up on the DL 51% of the time. Any pitcher who reached the thresholds were added to the spreadsheet.
Second, I found pitchers who had problems throwing strikes were also injury risks. Here are the 3 thresholds:
Stat, Threshold, DL%
Strike%, <60%, 45%
Zone% (Pitchf/x), <47%, 49%
NIBB%, >10%, 49%
Again, I have designated the pitchers who reached the injury threshold in the spreadsheet.
Fantasy owners shy away from spending too many resources on pitchers because of their health. With a little knowledge, pitchers can be drafted who have less injury risk.
Jeff, one of the authors of the fantasy baseball guide,The Process, writes for RotoGraphs, The Hardball Times, Rotowire, Baseball America, and BaseballHQ. He has been nominated for two SABR Analytics Research Award for Contemporary Analysis and won it in 2013 in tandem with Bill Petti. He has won four FSWA Awards including on for his Mining the News series. He's won Tout Wars three times, LABR twice, and got his first NFBC Main Event win in 2021. Follow him on Twitter @jeffwzimmerman.
Excellent stuff Jeff. I’m guessing Cliff Lee will be a bargain in this years drafts. He won’t be if he gets injured though.
It’s funny how we’re only one year removed from calling Madison Bumgarner and injury risk because of the huge jump in innings from ’10 to ’11. Now we’re ready to call him a top 5 least likely to be injured starting pitcher? I question that.
It’s almost like the innings jump is not as important as people make it out to be.
Jeff’s 2012 projections also included Bumgarner in the top-5 least likely to be injured, so while many people were saying he was a big injury risk, the projections have been consistent.
Bumgarner led MLB in slider usage %… yet he is among the least likely to be injury? I am clearly missing something.
The Bumgarner ranking (near the bottom in terms of DL likelihood) does not seem to make sense in light of what you’re showing as his high slider percentage, which you say correlates with being injury prone.
Looks like the DL Probability is based entirely on age, previous DL stints, and number of starts made. The high slider % was identified separately as giving an increased risk of DL stint, but I don’t think that the projection takes this into account. If you wanted to give a rough adjustment, since the high slider group was 7% more likely than average to hit the DL, Bumgarner could be bumped from 28% to 35% DL probability.
wow….the ever dependable Cliff Lee….gulp
Cliff lee went on the DL once in 2010 and once in 2012. In both years, he still pitched over 210 innings. Because of the way Jeff’s formula works, those two DL trips increase his DL % from 40.2% to 51.1%. So it’s even odds that he’ll have another DL trip like he had in 2010 and 2012, I guess. But there’s no telling how likely he is to have a more serious injury.
Jason Hammel? (More on the ‘likely’ side, I’m guessing)
Interesting stuff. Have you tried to distinguish between the short DL stints and the season-ending stuff? My gut instinct says that owners are so petrified about the possibility of TJ/rotators/etc that they undervalue some of the elite SP’s (and overvalue the healthy mediocre ones).
I’ve found that even a short DL stint for a pitcher is FAR better for a fantasy team than the sort of lingering play-through-it or DTD for batters. Missing 3-5 starts is always much cleaner than an injured batter who struggles for a month before the team decides to be honest about the injury. The latter is always roster hell.
It worked at pretty much the same times lost. If I do anything new on this front, it will be to dive a bit into RP.
i looked to see where Chris Sale appeared, since this is the first year he’d be on this list and he has mechanics that make a lot of people assume he’s an injury risk on sight. But he’s at 31% here, which is basically average. I suppose that’s where a list like this could be advantageous, bumping a pitcher who is talked about as an injury risk up a few spots since the numbers don’t support that accusation. Although similar things were said about Lincecum, and although his 2012 issues are still undiagnosed the concerns about mechanics haven’t been proven baseless given hindsight.
Sale actually comes in around 33%, which puts him on the lower end of the DL probability spectrum. Also, Lincecum did have some warning signs leading up to his disastrous 2012 (drop in fastball velocity along with a lower Zone %, which dropped from 50% in 2009 to 42.3% in 2011). Looking back, he was actually only at 31% DL probability going into 2012 (top-10), although the low Zone % would have been a red flag.
Point is, might be better to be cautious on Sale, but if you’re going to use Lincecum as a comp, you would expect to see some warning signs before the bottom drops out.
Sorry for kind of taking over the comments section, but also worth noting that all of the pitchers in this sample who had Strike % < 60% were also flagged for one (or both) of the other two "problem throwing strikes" categories (low zone% or high NIBB%), making it somewhat redundant (at least within this sample).
A couple things:
1) I don’t necessarily care about an non-arm injury. Yes they happen, but they are much more of a fluke and I’d argue they cannot be predicted whatsoever. See Rivera’s knee or Burnett’s head
2) I buy the breaking ball argument (assuming proper categorization of pitches) because it would make sense that I more physically demanding pitch would lead to wear. Though the strike percentage, its likely a trailing indicator. Brandon Webb is a great example of a guy that lost control, lost velocity then shut down — its indicative of an existing problem, not as much predictive.
3) Arguments around number of starts or innings, even pitcher abuse points, have consistently gotten nowhere in terms of statistical significance. I’d pose the hypothesis that injuries occur the more a pitcher, pitches tired — specifically when a guy labors through a 25-30 pitch inning. Just like any sports, when a pitcher is tired their form fails, and specific to pitchers, they end up shutting down their lower body and over-throwing. I’d argue its this effect that causes injuries.
I agree for the most part, Rivera’s injury was a complete fluke.
However a head injury like Brandon McCarthy’s is something I would worry about. He almost died and had to have brain surgery. That’s got to have some kind of effect on his pitching whether it’s mechanical, physical or mental.
I don’t understand why so many people say Madison Bumgarner is an injury waiting to happen, and then he shows up here as one of the lowest injury risks in the league! Can anyone explain?
Ok, scratch that post. I see the issue was already debated above.
Jeff,
Any difference between a 15-day DL and a 60-day or greater DL stint? Does your model reflect this?
Jeff: I’m curious about the Morrow number. 44% chance he ends up on the DL, despite the fact that 19-21% of his pitches last year were sliders (depending on whose data you’re using)and a 5-6% rate on curveballs thrown?
By two important criteria of your DL projections, it would appear that Morrow should be on the low end of the projections.
Am I missing something?
The DL projection % is based just on age, past injuries and experience and not based on the other factors (breaking balls and inability to throw strikes).
Morrow’s probably lies in his past DL stints.
Clayton Kershaw struggled with hip issues at the end of the 2012 campaign and has since stated that he’s changed his mechanics to avoid pain in that area. I know there are other factors involved, but isn’t it a major risk in itself for a pitcher to compensate for an existing or previous injury by altering his mechanics?
Great article. Thanks for the info, very helpful. BTW, if anyone needs to fill out a “2003 DD 1614”, I found a blank form here: “http://www.apps.dmv.ca.gov“