How does stress factor into a pitcher’s workload?

Tampa drops Game Two
Fan Confidence Poll: September 14th, 2009

Browsing through my RSS reader on Friday, I caught this bit by Tom Verducci of SI. From a guy with a namesake “rule” regarding pitcher usage, I couldn’t resist the title: “The problem with innings counts…” There are, of course, a number of problems with evaluating a pitcher on innings count and nothing else. That’s why the Verducci Rule is a rule of thumb: it is not intended to be strictly accurate or reliable for every situation. (From Wikipedia). Instead it’s a guideline. Surely teams use more advanced analysis to determine a pitcher’s workload.

This, of course, relates to Joba Chamberlain. He’s tossed 139.2 innings so far this year, after topping out somewhere around 120 innings a few years ago. The rule of thumb says a 30-inning increase raises a red flag, and Joba is fast approaching that number. The Yanks, for their part, are keeping Joba’s starts short now in hopes that they can keep his innings in check for the regular season.

Verducci makes an interesting comparison of Joba to two other young starters, Rick Porcello of the Tigers and Randy Wells of the Cubs. Both have about the same innings total as Joba, but there are factors which separate them. The one which concerns me most: plate appearances with runners on base. Those are considered higher stress situations. The pitcher has to worry about runners as well as the hitter, and generates less natural force by pitching from the stretch.

Chamberlain also leads the troika in overall pitches, and by a decent margin. So while he’s tossed a similar number of innings, he’s been under greater stress because of more runners on base and more pitches thrown in those innings. If we’re using innings as a measuring stick for work load, we certainly have to take these factors into consideration as well. They can help to more accurately judge how hard a pitcher works.

There are some other differences between Joba and his comps. Wells is a 26-year-old, so he’s out of Verducci’s range, which covers players 25 and under. His workload is less of a concern at that point, as his body is more physically mature. Porcello is just 20 years old and is in his second season of pro ball. Joba may lack experience, but Porcello has even less.

The comparisons are important, and I don’t think Verducci painted the whole picture here. It does show the high number of situations Joba has faced with runners on, and his high overall pitch count. But I’d like to see those juxtaposed with pitchers at Joba’s experience level, both past and present. I think that would give us a better idea of Joba’s actual work load. With access to these numbers we could whip up one of those fancy excel spreadsheets on which some fans like to play the games.

These numbers are a bit concerning. Joba will end the season with a sizable increase to his previous high in innings pitched, and far over his 100-inning total from last year. He’s throwing a good number of high-stress innings, and has a high overall pitch total. I wonder how these factors play into the Yanks overall evaluation of their struggling 23-year-old, and which others they’re using.

Tampa drops Game Two
Fan Confidence Poll: September 14th, 2009
  • darthdavid

    I find it odd that you speak of stress factor and go onto say he has thrown 120 innings?

    And all of a the big east = MLB or even MiLB, as far as stress goes??

    cmon fam.

    Joba threw 100 innings last season which was a career high.

    He has had a year where he hasn’t had his best stuff prob because he was maxed out post last year. And now they are throwing 60 innings ontop of it.

    Thats why I chuckled @ the whole Besides best efforts post you threw up the other day.

    • Charlie

      none of this makes any sense.. like, at all

      • Charlie

        by ‘this’ I mean what you wrote.. ie.. who’s fam? all of a the big east?

        • Drew the Pretty Pretty Princess

          fam is family, also a term of endearment.

          I don’t know what he said here:

          “And all of a the big east = MLB or even MiLB, as far as stress goes??”

          or here:
          “He has had a year where he hasn’t had his best stuff prob because he was maxed out post last year.”

          But I understood fam. lol

    • leokitty

      On top of all the other stuff you wrote that makes no sense, Joba’s career high is not 100 innings.

  • Drew the Pretty Pretty Princess

    Another day another dolla Joba post.

    Hopefully this isn’t an issue. He hasn’t been ostensibly bad. He’s been bad but in the same game, flashes his good stuff. Cough cough AJ cough.
    I’m not as concerned as you may be, I think the Yankees have done well to monitor his innings, stress and all.

    • Zack

      Yeah, cant even read them anymore. Happy its football season so the MSM can focus their time on that instead of Joba

  • Salty Buggah

    Well, this post kinda helps my (and several others) argument with alex gonzalez about high-stress innings being more detrimental than regular ones, which he denied even after a lot of good support.

    • Bob Stone

      Of course, Alex is probably gone now and not reading any of this.

      • Salty Buggah

        Of course not. Reading the open thread again, he said he hates A-rod. He explains after being asked why. Matt basically refutes his points. However, he doesnt reply.

        • whozat

          And his reasons were unsubstantiatable media narrative, basically.

          • Salty Buggah


      • alex gonzalez

        i read it. just some hours later than everyone else.

        • Doug

          “By god! That’s Alex Gonzalez’s music!”

  • NaOH

    The other factor that people seem to keep ignoring is that in the case of Joba his regular-season innings total is only being increased about 50 IP over his past high amount. Any additional innings thrown in the postseason are accumulated over an additional time period not afforded to a pitcher whose season ends after 162 games.

    When making these evaluations – and I presume teams consider this – there must be some attention given to the extra weeks during which a playoff pitcher is adding to his innings total. Had the Yankees been out of the playoff race, I imagine they would have handled Joba differently, most likely be letting him reach the prescribed innings total then just ending his season prematurely. Instead, knowing in early August that there was a good chance of the team making the playoffs, they probably adjusted his schedule and workload with October pitching in mind.

  • baravelli

    This is off topic, and I’m sure the guys here are on top of this, but I just wanted to submit a photo for consideration for the #12 magic number spot:

    • whozat

      Email them.

      1) the authors are very responsive to email here
      2) they don’t necessarily read every comment
      3) the community here prefers to keep threads on-topic, with the exception of the open thread (which is, by nature, about all topics!)

      • baravelli

        Sorry for the breach of etiquette. I didn’t see the tip submission box before I posted. Now I’ll know better, thanks. (It is a good #12 picture though…)

        • whozat

          no worries :-)

          I’m just waiting for a flight and really bored.

  • Makavelli

    It’s not just Joba we have to worry about…

    AJ Burnett has been horrendous. In his last 5 starts he has a 7.67 ERA and opposing batters are slugging .529 off him with 8 home runs. And while 8 walks isn’t that great…it’s not THAT bad in 5 starts…for him anyway.

    As for Joba, he’s been tweaked so many times it’s hard to get a steady groove when you don’t know what’s going to happen next. It’s hard to pitch to your best ability when you know deep down everyone is counting your pitches, innings, etc. You start, perhaps, trying to do too much…overthrowing…try to do as much as you can with as little time as you have. It’s hard to just concentrate and do what you’d like to do when that’s the case. And I truly believe that’s the biggest problem right now. I don’t think it’s entirely fatigue or anything of that nature. I think if they just let him loose he’ll have better results. Although, I do believe that when in the playoffs and he is let go to pitch whatever he needs to…fatigue/mis-use/some getting use to may then take an affect on Joba.

    But they have to do what they have to do with Joba. In his last 4 starts he has a 9.00 ERA and opposing batters are slugging .508 against him while he’s only given up 1 home run. This isn’t good.

    Combined, these two pitchers are 1-5 with a 10.65 ERA in their past 9 combined starts.

    It’ll be hard winning games in the playoffs against MUCH better pitching and teams as a whole if these performances continue.

    • Say Hey Willie

      I would like to see AJ and Joba turn it around as well, but “MUCH better pitching and teams as a whole” is not just ridiculous it is totally nuts. The Yankees have the best record in baseball and they play in the toughest division. It is very hard to argue that there are much better teams out there.

      • Bill R

        I don’t think he means better than the Yankees he means that we will be playing “playoff” teams as opposed to getting smacked around by the completely out of it Orioles. If things hold steady we’ll see Detroit in the First round and In my honest opinion I’d much rather see a Pettite vs. Jackson game #2 and have a Porcello or Bonderman vs. AJ for a game 3 any day of the week.

        • Makavelli

          Disagree. Pettitte has MUCH better numbers on the road and AJ has MUCH better numbers at home. Why would you make so that both of these pitchers are pitching where they are extraordinarily worse?

          • Bill R

            yeah but Lefties have a better ERA at Yankee Stadium so why not go Lefty, lefty at Home then pitch AJ in game 3?

    • MikeD

      I’m taking the optimistic side with AJ. He is a streaky pitcher. Timing suggests he’s about to start a hot streak. So at least for today, I’m going with the glass half-full approach.

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