Norichika Aoki Deserves a Starting Job

When the Milwaukee Brewers added outfielder Norichika Aoki to their roster this past offseason, I thought it was a curious move — the 30-year-old outfielder was one of Japan’s better hitters and by my anticipation deserved at least a large platoon role. Yet the Brewers intended on using him in a bench role.

In his final and worst season in the NPB, Aoki was still one of the league’s best hitters. And looking at his final five seasons in Japan’s Central League, we see he was consistently a dominant hitter in a league typically starved for offense:

Aoki’s wOBA

2007 .395 127 .310
2008 .400 131 .306
2009 .371 123 .301
2010 .408 129 .316
2011 .320 115 .277

All wOBA+ numbers relative to the Japanese CL.

Aoki has been getting more playing time lately, but now it’s time for him to get all of it.

Entering play on Thursday, Aoki sports a .370 wOBA and 135 wRC+ — created largely from his strong .380 OBP. He has walked at a decent rate (7.6% BB-rate) and limited his strikeouts (12.4% K-rate), but his BABIP (.364) is noticeably above league average, so we have to account for that.

In the past, when a player’s BABIP was crazy town banana pants, we just said, “Oh well, he’ll regress,” and threw the data trash-wise. Now, with the assistance of FI wOBA, we can reasonably predict what his offensive production will be given a change in BABIP.

First, though, we need to predict what his BABIP will come down to. One such tool is slash12’s xBABIP calculator, which is an excellent asset and something I use in the De-Lucker chambers, but in general, my preference is to use a player’s history when possible. And though Aoki is a rookie by MLB standards, he is still a veteran of pro ball, which brings us again to his NPB numbers:

Aoki’s BABIP

2007 .365 120 .304
2008 .363 119 .305
2009 .319 109 .294
2010 .382 125 .306
2011 .317 110 .287

He currently has an above average BABIP in the MLB, but he always sported an above-average BABIP in the Japanese CL too. Currently, in the MLB, he has a 124 BABIP+ while his BABIP+ over his final five seasons in Japan averaged out as 116.

If his BABIP lowered to meet his NPB numbers (which I would not expect him to match), then he would maintain a .340 BABIP. At a .340 BABIP, Aoki would sport a .334 wOBA, according to FI wOBA. At a .330 BABIP (113 BABIP+), he drops to .327 wOBA.

Here is a contingency of possibly BABIP scenarios:

And if you prefer the Plus Method of analyzing data:

So unless Aoki completely changes his batted ball profile from his days in Japan — and hey, it’s a very different run environment, so anything is possible — he should be able to muster at least above-average offense.

Moreover, Aoki has thus far shown a capacity for hitting more than a few triples — leading the Brewers outfield with 3 three-baggers despite playing the least. As such, FI wOBA — which inherently undervalues doubles and triples hitters — is perhaps offering the most pessimistic of forecasts here.

If the Brewers do indeed choose to offer Aoki consistent playing time, they could even do so without even taking playing time from the other outfielders — Corey Hart could slide to first, Ryan Braun would remain in left, and Carlos Gomez / Nyjer Morgan / Tony Plush could man center field.

So unless the Brewers think Travis Ishikawa can really maintain his production, or think any of their other thus-far underwhelming first baseman can out-WAR Aoki, then there should be little in the way of a starting — or at least 60% platooning — Aoki.

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Bradley writes for FanGraphs and The Hardball Times. Follow him on Twitter @BradleyWoodrum.

26 Responses to “Norichika Aoki Deserves a Starting Job”

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  1. tacoman says:

    What on earth happened to the offense during the 2011 Japanese PCL season?

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    • They instituted a new league-wide baseball. In the past, each home team had their own ball, but the new ball was — if I recall correctly — slightly smaller than the MLB standard baseball and considered more slick.

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      • Nate says:

        It was designed to imitate the MLB ball, which is used in international tourneys like the WBC. The smaller, slicker one was one of the more common ones used before the switch…at least from what I read. I’m interested to see if this switch leads to being able to make more accurate predictions about NPB players before they come over to MLB.

        Here’s an article about it:

        I think there was also a pretty good one in the NY Times or Japan Times, but I can’t find the link now.

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  2. It’s worth noting that FI wOBA currently undervalues Aoki by as much as 20 points of wOBA. That’s a HUGE gap, but it assumes that Aoki will continue to hit triples at his presently outstanding rate.

    He’s currently hitting triples at a 2.86% rate — good for fifth best in the league (min. 100 PA).

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  3. BillyF says:

    Mr. Woodrum: Aoki stayed in Japan’s CENTRAL LEAGUE his whole career before posted. Where did that Pacific Coast league come from? I know you might like your Matsuzaka (Seibu, PL), Okajima (lastly stayed in the J-Ham, PL, but he had most of his career at Yomiuri, CL), and our cute Persian (Darvish from J-Ham, a.k.a. Nippon Ham), but there’s no such league as “Pacific Coast.”

    It’s simply: Pacific League. No coast. Unless you were coasting with rum and stayed in the woods too long, wikipedia could be helpful:

    Sorry for the humor. I could not resist. But I’m kinda sick and tired of baseball ignorance dealing with foreign leagues and international tournaments. There are proper ways to call them, the least we can do as Major League fans.

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    • Whoa, geez. Oversight on my part. I’ll go ahead and fix it so that you don’t have to be “humorous” anymore.

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      • thouston says:

        “also dude, Pacific Coast League is not the preferred nomenclature, Pacific League, please”

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      • BillyF says:

        Looks like your supporters are not throwing enough “red flags” with 9 minuses. I guess fangraphs still welcome other fans with an opinion but not agreeing you columnists’~

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      • BillyF says:

        Mr. Wood-rum, please also read my reply to “joser” below. It’s IMPORTANT to know the league when you are bringing up their numbers. You have no excuse to make repeated mistakes.

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    • Sooted72 says:

      i’m not sure ‘humor’ means what you think it does

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    • Japanese Yakov Smirnoff says:

      In Japanese baseball, data analyze you! What a country!

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    • Ben says:

      It was obviously just a mix up with the minor AAA Pacific Coast League. You come off less humorours and more mean than anything.

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    • joser says:

      On the scale of what passes for both humor and (especially) mean-ness in FG comments, this is pretty minor AAA PCL stuff.

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      • BillyF says:

        Minor? Then why are you responding me? I won’t call USA “Canada,” although they are both occupying a large portion of North America. One thing I found out about fangraphs posters and some columnists is that you guys go one direction and never looked the other hard enough. When you consider performance in Japanese baseball, and “translate” them to American ball, you lack the context. Darvish never walked more than 3 per nine inning his career in PL, why he overloaded the bases here? Iguchi was almost retiring his last days with the Phillies, but he had a resurgence in PL, known to be a pitchers-league in the past.

        Things change when players cross the Pacific. The Way of Thinking must change with them.

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      • BillyF says:

        And you will fail to see the context if you refuse to identify them correctly. It’s important to name USA as USA, not another country beside Canada. Japanese ball is not AAA ball, I thought educated fans on fangraphs had past that stage of ignorance already.

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  4. funketown says:

    I haven’t been overly impressed by Aoki’s defense. From what I’ve seen, he doesn’t have very good speed in the outfield though he seems to take pretty good routes. The downgrade from Gomez to Aoki in CF is pretty large.

    It makes a whole lot of sense to just slide Hart to 1B, play Aoki in RF and then split the CF gig between Morgan and Gomez. They’ve toyed with that option against LHP (I’ve heard repeatedly that Aoki hits LHP very well).

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    • Cecil Cooper's Twin says:

      He hits very well against lefties and with Hart doing a good job at 1B and T-Plush starting to hit a bit, I see RF becoming his predominant home for the near future.

      It has been nice to see base runners in front of Braun in the 1st inning, as opposed to April-early May when it was always zero on, 2 out when Braun hit the dish in the first inning.

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    • Bob says:

      Gomez is a really good defensive CF, so it shouldn’t be a surprise that there is a dropoff is Aoki plays there. But I definately think that Aoki should be getting all the playing time ahead of Morgan (if there needs to be a choice between the two).

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  5. Well-Beered Englishman says:

    The Nationals should be kicking themselves.

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    • John C. says:

      Absolutely. Even given that they thought that they had outfield depth (with Morse and Werth presumably healthy), there is utterly no reason to have a team having to choose among Ankiel, Bernadina and Nady for one of their starters.

      In the “better to be lucky than good” department, though, it’s quite possible that if they had picked up Aoki they would have kept Harper in AAA longer, until he “mastered the level.” Considering that Harper has been one of their primary offensive threats since he came up, it may have worked out OK for the team. But I was on the Aoki bandwagon when he was available, and was disappointed when the Nats didn’t make a play for him.

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  6. Snowblind says:

    Hey Rockies, watch me pull a rabbit out of this hat… naw, seriously, Rockies, would you like something for that Aoki you’re not using? The Mariners would LOVE to have a set-it-and-forget-it left fielder.

    Getting tired of the rotating cast of guys like…

    – Wells (underappreciated and not given a shot, like Aoki apparently)
    – Carp (hitting potential, decent arm, slow legs)
    – Liddi (playing out of position because Mariners, decent arm and bat, fields like a bus)
    – Figgins (UGH)
    – Peguero (Guerrero power, Guerrero strike zone, Olivo contact… fielding routes like Billy from Family circus).

    And hey, one more dino-buddy for Ichiro to go along with Kawasaki might make for a nice sendoff, in the event that this season ends up being the Ichiro farewell tour.

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    • Snowblind says:

      CHRIST this board needs an edit feature. To go with smarter commenters. Starting with me.

      Brewers! Brewers! Not Rockies.

      Bah, I’m an idiot.

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  7. robby says:

    i think he will be getting more playing time as he proves he can hit in just about any situation. the biggest issue is that Hart has said he doesnt want to play 1B, but has said he’ll be helpful if needed there, so sticking him there fulltime going forward is doubtful to happen

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  8. mike says:

    Prediction: More doubles, lower BABIP, miniature american flags for all!

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