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Porcello’s Inning Count

As the Tigers continue to move towards their probable playoff birth they have to start thinking about their playoff rotation. Justin Verlander and Edwin Jackson form a strong top two. After that Jarrod Washburn has, not unexpectedly, seen his performance come back to earth and will have his next start skipped in hopes of alleviating some knee pain. Still you have to pencil him in to the rotation. In a four-man playoff rotation they have little choice but to go with Rick Porcello as the fourth pitcher. The alternatives, Nate Robertson and Armando Galarraga, just inspire too little confidence.

Porcello is having a circa-2007 Chien-Ming Wang type season. Very poor K/9, mediocre K/BB but lots of grounders. The end result is an ok performance, no doubt aided by Detroit’s excellent infield defense. The problem is that Porcello is just 20 and has already thrown ten more innings than last year, if he takes 4 or 5 more turns through the rotation in the regular season he would be up to at least 30 innings more than last year. The Verducci effect suggests that pitching 30 or more innings more than the year before drastically increases the chance of injury to a young pitcher. The Tigers would, of course, ease those guidelines for playoff innings, but it would be nice if they could limit Porcello’s regular season innings, as the Yankees are doing with Joba Chamberlain.

Unfortunately the Tigers’s rotation is not healthy, or deep, enough to do that in the thick of a still not totally settled AL Central race. Nate Robertson came off a AAA rehab stint to enter the rotation in place of Armando Galarraga who was out with elbow inflammation. Now Galarraga has to come straight back to the majors rather than make a scheduled start in AAA to take Washburn’s spot. So there is not much opportunity to skip Porcello’s starts at the moment.

Hopefully the Tigers can wrap up the division soon or get Robertson, Galarraga and Washburn simultaneously healthy, so they can limit Porcello’s innings down the stretch. If not they could, if they go on a deep playoff run, put a dangerous number of innings on Procello’s young arm.


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29 Responses to “Porcello’s Inning Count”

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  1. joe says:

    The Verducci effect is a farce. The only reason an increased inning workload can add to the likeliness of injury is a result of flawed mechanics increasing the stress on the body. Ubaldo Jiminez and Lincecum have great mechanics, while players like Hamel’s don’t, so it’s no surprise how their seasons have gone so far.

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    • lincolndude says:

      I seem to remember a post on fangraphs around the start of the season that really tore into the Verducci effect.

      He certainly has not examined his effect in a scientific way.

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    • joser says:

      So by your analysis, unless Porcello’s mechanics are flawless, the Tigers would be smart to assume Verducci’s effect is not a farce. How certain are we (and more to the point, how certain are they) that Porcello is flawless enough to evade the effect, farcical or not?

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      • joe says:

        Irrelevent to what i said. And no, i did not say flawless mechanincs, obviously by flawed i meant Kerry Wood and Chris Carpenter flawed. The “effect” has been proven time and time again to only apply to those who learned the wrong way to pitch.

        And if Porcello does have bad mechanics, he will get hurt eventually, probably soon, but how many innings he pitches this year won’t change that.

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      • Rob in CT says:

        Hey Joe, when was the V effect been “proven time and again to apply only to those who learned the wrong way to pitch.” Are you referencing a study of some kind? If so, do you have a link handy? It sounds interesting.

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    • don says:

      Hamels doesn’t have an apostrophe in his name.

      He’s also exactly the same pitcher he was last year except for BABIP, so he’s really an exception to the Verducci affect, not the rule.

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    • Gary says:

      Did you just praise Lincecum’s mechanics?

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    • Richie Abernathy says:

      How are Hamels’ mechanics so much worse than Lincecum’s? By the way, Hamels is not injured. He threw a two hitter in his last start, in case you’re scoring at home.

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  2. 310ToJoba says:

    Is a playoff “birth” more meaningful than a playoff “berth”?

    I had never really realized just how shallow the Tiger’s rotation truly is. More surprising there’s nobody on their 40-man who could even be considered remotely appealing as a spot starter (a la Chad Gaudin).

    Also, agree 100% that the Verducci effect is magnified by players having bad mechanics *and* increased workload. This is the same Verducci who wrote a glowing piece about Lincecum’s mechanics…

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  3. Anonimouse says:

    Robertson has been lights out since his mid-season surgery, including stops at both Toledo (AAA) and in two starts with Detroit. If he can give the Tigers even just a league average performance in the remaining 5-6 starts over the last month, that relieves a lot of the pressure the Tigers rotation faces. After skipping Washburn’s turn this weekend, the Tigers could then use Robertson and Galaragga and Robertson to similarly skip Porcello and/or Jackson once through.

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  4. The Nicker says:

    “Hopefully the Tigers can wrap up the division soon or get Robertson, Galarraga and Washburn simultaneously healthy, so they can limit Porcello’s innings down the stretch. If not they could, if they go on a deep playoff run, put a dangerous number of innings on Procello’s young arm.”

    I would imagine this is exactly what the Tigers would like to do, particularly as it becomes clear that they will win the Central. Provided they lock up the central, they could essentially “throw out” Bonine to make a couple starts in the last two weeks, or even Zack Miner. The bottom line, provided they maintain a 5 game lead over the next two weeks, all of these workload problems on Galarraga, Porcello, and Washburn will be alleviated.

    “The Verducci effect is a farce.”

    Obviously it’s not exact or scientific, but it seems pretty clear to any statistician that upping the innings of a young pitcher considerably will increase his chances of being injured.

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  5. Dick Pole says:

    Jeremy Bonderman will be part of the Tigers September call ups. They’ll rest Porcello down the stretch if Bondo can make a start or two in his place.

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  6. Dave says:

    I believe the “Verducci Effect” is a phenomenon that counts major league innings, not innings from the minor leagues.

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  7. B says:

    Ugh, I hate the Verducci effect, because why wouldn’t he actually take the study to the next level? Instead of simply looking at arbitrary and probably meaningless baselines, why not do a statistical analysis to try to figure out how much extra chance of injury comes from each extra inning. It really wouldn’t take all that much work. I can understand initially doing it how he did, but now that he has this huge scientific sounding effect named after him, the least he can do is follow up with some real data to support his theory.

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    • Rob in CT says:

      I think you have to look beyond just innings. There are innings and there are innings, right? A 6-pitch 1-2-3 inning is not the same as a 30-pitch inning with walks, hits, etc.

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  8. Rob in CT says:

    The V effect is obviously a general rule, not a precise equation. In the aggregate, though, it seems to have a lot of truth to it.

    I would imagine the Tigers should be looking at:

    a) how many pitches/inning Porcello is throwing.
    b) how many innings of 25+ pitches he’s thrown (or whatever cutoff you want to use to denote a “high stress inning”).
    c) how his mechanics are holding up during said high stress innings and late in games.
    d) his prior injury history

    In Joba’s case, he’s already had a (thankfully minor) shoulder issue. The Yanks are right to be careful (though one can debate exactly how they should do it).

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  9. Matt B. says:

    Porcello reminds me a lot of Aaron Cook.

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  10. blackoutyears says:

    “Porcello reminds me a lot of Aaron Cook.”

    Hmmm. You and Keith Law apparently.

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