Moving Starlin Castro off of SS would be biggest error of all

There's been some chatter early on the season that Starlin Castro should change positions.  With every error, the boo birds come out and talk ramps up about how Castro doesn't belong at SS.   The claim is that he costs the team runs and ultimately wins.

The problem with that claim is that it's as inaccurate as a few of Castro's throws have been this year.

And I don't mean inaccurate in the sense that you can  live with Starlin Castro's defense at SS because of his great offense at a premium position, though that part is true.

I'm saying it's wrong to say that Castro has been a liability on defense this year.  Period.  In fact, Castro has been an average to slightly above average SS so far this season.  I'll get back to that in a bit.

If you focus solely on errors, you miss the bigger picture.  Yes, he will make errors from time to time.  Most 22 year old shortstops do.  He needs to improve his footwork.  He has worked hard at it but still gets sloppy at times on routine plays.  It takes time to re-learn mechanics.  He will get better once the new approach/footwork he has been taught this offseason become natural and not mechanical.  At some point, it's going to click and he won't think about proper footwork.  He'll simply do it.

But until then, his range, hands, and arm strength more than makes up for his occasional errors.  Here's what I mean...

Thus far Castro's RZR is at .886.  What's RZR?  It stands for Revised Zone Rating and it measures, “the proportion of balls hit into a fielder’s zone that he successfully converted into an out”.  That is what you ultimately want your SS to do.

Let me put that RZR into context.  An above average RZR is about .860.  A great one is about .900, so we can say that Castro's range by this measurement is very good.  But that explanation doesn't do Castro justice.  To understand how good that is and how much improvement he's made in this area early on, no regular SS last season had an RZR that high.  Not Elvis Andrus.  Not Troy Tulowitzki. Not Jimmy Rollins.  Not Jose Reyes.  None of them.

I'm not saying Castro has better range than those players or will sustain that RZR over a full season. It is a small sample size, but it's an improvement as far as Castro's individual play so far this year.  His defense this season is what's being questioned, but to this point the numbers indicate that he his defense hasn't hurt the team overall -- and it may even be helping them.  Castro's range runs (RngR) of 3.2 more than offsets his error runs (ErrR) of -2.3.  In other words, his good range this season has been worth more runs than his errors have cost.

His UZR (Ultimate Zone Rating), which takes all defensive aspects into account, including errors, is a positive 0.1 this year.  For all intents and purposes that is an average SS, but project that to 150 games (UZR/150) and Castro's rating is 5.5, which would make him an above average defender.  In fact, that rating would have ranked 9th last year among shortstops with more than 1000 innings.

Intuitively, we all know that great range can make up for a few more errors.  To put it in an oversimplified way, you'd rather have a SS that makes 10 more errors but gets to 100 more balls.  That's a net gain in outs of 90 over the course of a season.  It makes sense that you'd want a SS that creates as many outs (and thus saves runs) as possible on defense.  RZR and UZR/150 are just more sophisticated ways of measuring that basic premise.

So, although the throwing errors may cloud things up a bit, it does appear that Starlin Castro is making progress.  Advanced defensive metrics indicate that not only has Castro improved substantially over last season in terms of range, but he is actually playing a very solid SS overall over the first 21 games this season -- errors included.

Castro's offense is already a big bonus at what is considered a premium defensive position, but if he can continue to play solid to good defense while cutting down on his errors, he can become an elite player in this league.

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  • Great Info John. I couldn't agree more that the Cubs should leave Castro at shortstop no matter what. The value he brings with his bat at that position is ridiculous.. And you can tell the talent is there. He just has a hard time paying attention. Hopefully he grows out of that.

  • In reply to JR Cubbies:

    Thanks JR!

    I think part of it is focus and part of it is thinking his way through too much. When he makes throws on the move, his footwork is fine -- but on routine throws his feet get caught in a less than ideal position to throw.

  • Hmmm, something is odd...that RZR (by the way, probably a typo, you described it as Revised RANGE FACTOR), is 2nd WORST out of 30 SS, with only Erick Aybar worse...

  • In reply to Norm:

    Nothing wrong. You're changing the parameters of what I wrote. Look up Fangraphs (RZR up to .894 by the way) and look up the guideline chart in that glossary as far as where that ranks. Look up what others SS did in 2011, which is what I referenced in the first place.

    And don't you think it's just a wee bit odd that he would have a positive range runs and UZR with the 2nd worst range amongst SS?

  • In reply to John Arguello:

    I hear ya, but Fangraphs is ranking Castro's RZR 29th out of 30 for this year.
    There are four guys at 1.000
    And 23 guys over .900
    I can only assume its because of the limited sample...but RZR has Castro as the 2nd worst SS right now.
    As for why UZR would show positive, I'm guessing its because of his OOZ (out of zone) plays. He's 3rd best.
    Conversely, Jhonny Peralta's RZR so far is .976 (7th best) but Peralta is -3.5 UZR, which is 2nd worst.

  • In reply to Norm:

    I know what you mean but the RZR in a vacuum is above average. The OOZ has been great, which I should have mentioned as well in the article.

    The basic idea here is that the improved range so far this season has outweighed the error factor.

  • In reply to John Arguello:

    Should also mention that Castro's OOZ is 7th in baseball since 2010, so it's pretty safe to assume that isn't a fluke.

    His RZR in that time is just .793, so while it is still behind other SS's, it's still much better than it has been in his career so far.

  • Castro's career UZR is -10.7, a period covering 305 games. I certainly don't rule out that Starlin is improving as a defender, but it's still far more likely that he's a below average defensive SS moving forward.

  • In reply to Eddie:

    The arm, range, and hands are all there -- you either have it or you don't, that cannot be taught. Sloppy footwork has held him back, but that can be learned.

    I don't see anything physically that indicates he can't be at least an average SS. And this may be a small sample size, but it's also completely unbalanced going the other direction. The error rate cannot continue to be that high. The improved range might be for real or it may regress, but the errors will also go down as well.

  • This is the result of a great player being rushed to the Majors. They should've kept him there another year, but Hendry was trying to save face with the new owners.

  • In reply to lokeey:

    Agreed. He's just 22, the age of a typical high A ball player or good AA prospect.

    He's still learning the position at the major league level. The skills and athleticism to play the position are there.

  • For me, it is not whether on not he is a capable SS - he is. I believe that Jeter made a ton more errors at nearly the same stage of development, and he was still inthe minors.

    My issue is still with the optics of his game, when he is on the field, either with the glove on or bat in his hand.

    There is still something about his makeup that troubles my baseball sense. I have watched him over the past few weeks closely and the nagging suspicion that he will not ever mature into a big league force still naws at me.

    Wish I could pinpoint the reason, but thus far it has eluded me.

  • In reply to JK1969:

    The eyes sometimes fool us, which is why I like to turn to numbres when I'm in doubt. But I think even the eye test shows Castro has improved his range. He's made a few remarkable plays already this year.

    I'm not sure what you mean by Castro's makeup. He has been working hard on his defense all offseason, has taken to instruction very well...the only thing I see is he does show some of his frustraton when he makes an error. But he's just 22 and I don't think it's that unusual to see someone that age get down on themselves when they make a mistake.

  • I think he has matured quite a bit this year. It shows on balls in the air, he is taking charge and running them all down, much like an Ozzie Smith did. As Jose Gonzalez of the Brewers(great fielding ss) said, he will be one of the greats, to be able to accomplish what he is at 22 is amazing.

  • It's all about perspective. To do what he's done at ages 20-22 is remarkable.

    High compliment coming from Alex Gonzalez. He's among the best out there with the glove.

  • castro is 22 years old. our top prospects are 22, 23 respectively sitting in triple A right now, and i promise they won't be perfect when they come up. people complaining about castro and his inability to play shortstop need to step back and wait til hes 25 to decide if thats really the reality. if he was allowed to spend the better part of the last 2 years in the minors im sure his defense would be spectacular, and he'd most likely be lumped into that elite-of-the-elite prospect group with mike trout, bryce harper and matt moore.

  • In reply to jshmoran:

    Agreed. Let's give some time. For right now, he's holding his own and his good range makes up for some of the errors.

    He's nowhere near his peak years. He should get better. The only thing that will move him off of SS is if he outgrows it and loses range.

  • Great article. What do you mean when you say he's a "true shortstop"? You didn't here, but I've heard you use the term before.

  • In reply to Carne Harris:

    Thanks! By true SS, I mean he's a guy with the athleticism, range, arm, and hands to play there. As Kevin Goldstein once said, there are less than 30 true SS's in the majors. I feel that Castro is one of them. If he can cut down on the errors, then he's got a chance to be a solid defender with a well above average bat for the position.

  • John, saw that the Tigers were considering sending down Max Scherzer, and other than Verlander and Smylie, their starters have been a disaster. Think Theo and company are on the phone about Garza, or is he pitching so well they really would want to keep him at this point? He is the kind of starter that could put their team over the top.

  • I do think teams are picking up the phone right now. We may have more on that later today.

  • Great article John. I think you summed it up how much progress Castro has made.

    Next question, which you've asked before, is when are they going to lock him up to that Longoria-type deal?

  • In reply to Cub Fan Dan:


    I'm hoping they look into locking him up long term by this offseason.

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    Great read John. I agree, people tend to jump the gun too early on players like Castro. As you said based on his age the guy should be in AA at the most. In my honest opinion I believe it is idiotic to believe he has reached his ceiling at the SS position or in any facet of the baseball field. When people say he should be move from SS I only ask "You do realize the kid is just 22 right???'' he still has an abundant amount of time to get better at the position, even though he is above average imo.

    on a side note is their a reason Volstad is starting todays game and not Shark? I thought Shark was always after Garza as the 2 and 3 (now 1 and 2 with Demp out) maybe I missed something.

  • In reply to Marcel Jenkins:

    Thanks Marcel. I think Castro deserves a little patience especially considering that, statistically, he hasn't really hurt the team with his defense this year. He just has so much value as a SS.

    I don't know why Samardzija was pushed back. That's interesting. If I find out, I'll post the reason.

  • In reply to John Arguello:

    They are just giving Samardzija an extra day of rest (this is Volstad's normal rest time).
    With Shark a RP in previous years, I think they'll do this occasionally.

  • In reply to Norm:

    Thanks Norm. That makes sense. On a sad, related note, it now means I'll probably get Volstad instead of Samardzija when I go to the game this Saturday.

  • In reply to John Arguello:

    Actually, John, I think that is excellent. Given that you are the Cubs' rabbit foot, your presence will get Volstad off the schneid.

  • I chose the word makeup because I am having trouble articulating what 40 plus years of watching bb has taught to understand - not perfectly, by any stretch of the imagination, but nonetheless, I tend to pick up on a lot of non baseball signals about a player.

    Castro has the tools, the god given ability, but I beleive that he MAY (yes I said may) end up lacking the necessary grit and determination that all players need to make for a long sustained career.

    Someome may take him under their wing, or he may find it in himself, but for the moment, I do not see him growing into and maintaning a high level of excellence.

    I guess what I am trying to say is that I believe he has a reasonable chance of flaming out before he reaches amd maintains his full potential.

    I do not wish it to happen, nor do I know that it will happen, but I remain unconvinced of his l/t viability as a major league player.

  • In reply to JK1969:

    With all due respect, we'll have to agree to disagree on this one, JK. First of all, I think he's very determined. He works as hard as anybody out there.

    Nobody is a sure thing, but I think Castro's bat is about the surest thing there is on the Cubs right now. They have no other player with that kind of ability right now, not Jackson or Rizzo or Baez. If Castro was still in the Cubs minor league system, he'd be their #1 prospect and it wouldn't even be close. Gritty is a nice bonus, but it's no substitute for pure talent combined with aptitude/instincts for the game. I'll take that over grit any time.

  • Shark is given an extra day of rest so they flip flopped Volstad so he is on his regular schedule.

  • In reply to John:

    Thanks John. I thought it'd be something like that. The more they can rest Shark and keep his innings down, the better.

  • 2nd base requires the same range. The only difference is that the throws are much shorter, and easier to make. We would still be able to take advantage of Castro's magnificent range, but it would also cut down on his throwing errors. All of this would be a reasonable argument not to move him to 3rd or the outfield, but why not place him at 2nd?

  • In reply to elusivekarp:

    Part of range is your throwing arm. Let's say Barney has the same lateral range that Castro does (he doesn't, but for sake of argument we'll say he does), he doesn't have the arm strength to complete all the plays that Castro can.

    SS requires a player with the complete range of skills that Castro has. Moving him to 2nd wastes one of those skills. There's no question Castro has more value at SS, and moving him over a few throwing errors in April in his age 22 season would be short-sighted.

  • In reply to John Arguello:

    And the bottom line is he's still been a positive asset at SS so far this season, why would you replace a SS who statistically saves you more runs than he costs?

  • In reply to John Arguello:

    I agree with your argument, but my thinking is that Castro is just one of many SS prospects the Cubs have. What happens when Lake or Hernandez get called up in the next few years? What if it turns out Baez does have the range to be a SS? Wouldn't it make more sense if Castro moved to 2nd for one of those guys?

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    You know, I was thinking a little that having Castro move to a different position would help this Cubs team greatly. But after reading your superb article I'm all for Castro continuing at shortstop. Also, the Cubs look alot better now then in the beginning of the season. Hopefully they continue. Go Cubs!

  • In reply to Danny Guerra:

    Thanks Danny! I think he at least deserves a shot. He has improved despite the errors.

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    Since someone brought up Jeter, I looked it up.

    He played 160 games at AAA (35 at age 20 and 123 at 21) and made 36 errors.

    His age 22 season was in the bigs, and he made 22 errors.

    Let Castro play. He's getting better, and like you say, he's got the skills. If one of the other SS prospects makes it (big IF), then we can figure out what to do at that point. For now, let him play and learn.

  • In reply to brober34:

    Exactly Brober. If the Cubs had a lights out SS in the minors, it'd be one thing. Maybe some don't like Castro because of the errors, but he's better defensively than Lake, Baez, or pretty much any SS they have in the minors except for maybe Marco Hernandez. But since Hernandez isn't hitting and is only in low Class A, we don't need to worry about it at this point.

    I even think Castro will be a better SS than Barney would be. I'm not sure Barney has the arm to make enough plays at SS. His arm is fringy, although he gets ride of it quickly and his range is okay, but more due to positioning than lateral quickness. In other words, Barney is as good as he's going to get and I'm not sure it's good enough -- and that's not even considering whether he's a long term starter at any position based on his bat.

    It just makes no sense to me from any perspective. The kid is 22, has been playing better of late. He has too much potential to be an impact player as a SS if he can just play average defense.

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