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The biggest news to hit the yuletide airwaves was the official posting of star NPB pitcher Masahiro Tanaka. From now through January 24th, teams are expected to scramble for the opportunity to pay the newly-adjusted $20 million posting fee and sign the right-hander. The new import process all but assures that Tanaka will receive a heftier contract than previous NPB standouts Yu Darvish and Daisuke Matsuzaka, since the bidding war now benefits the player rather than his old ballclub (much to the chagrin of Tanaka's squad, the Rakuten Golden Eagles).

Tanaka was the ace of the NPB champion Eagles, and he came in to pitch the last inning in the final game of the Japan Series to secure the championship trophy for Rakuten. The rare relief appearance came one day after an 160-pich outing in a complete-game loss to the Yomiuri Giants, and Tanaka's heavy usage patterns of the past could be a factor that affects his future performance. He has averaged a full eight innings per start over the past three seasons, frequently exceeding 130 pitches even when he fell firmly into the icy clutches of the early-20s injury nexus, which tempers the enthusiasm generated by the “25” in the age column of his baseball card.

Tanaka received a lot of acclaim in 2013, with a stat line highlighted by a perfect 24-0 record and a 1.27 ERA, including a strikeout-to-walk ratio of 5.7 to one in 212 innings pitched. He has posted a sub-2.00 ERA in each of the last three seasons (the first two of which, especially, saw suppressed run-scoring due to a less lively ball). More of a control artist than a big bat-misser, Tanaka has also made his mark by limiting the long ball, with only 18 home runs allowed in his last 611 innings of work (0.26 homers per nine innings). League context weighs heavily in this case, though, with NPB's Pacific League averaging just 0.56 HR/9 over the same period (the MLB average from 2011-13 was 0.98 homers per nine innings).

The most glowing statistic attached to the right-hander is a ridiculously low walk rate, which has sunk to 3.3 percent during NPB’s recent small-ball era. Prior to 2011, Tanaka’s career walk rate was 6.7 percent, though it was trending down. The more concerning detail emerges when one looks at the escalating rates of free passes for the other top pitchers to make the transition from NPB to MLB; Darvish went from a 5.4 percent walk rate in his final three years in Japan to a 10.2 percent mark in his first two years stateside, while Matsuzaka took his three-year NPB average of 5.7 and became a 10.9 percent dispenser of free passes in his first three years in the majors. History has not been kind to the control rates of NPB hurlers, and a pitcher who earned his paycheck by limiting walks and homers could be greeted with a rude awakening upon hitting MLB.

However, Tanaka’s stuff is legit, with a fastball that sits 90-92 mph but spikes to 96, a sharp breaking ball, and a splitter that disappears late on its path to the plate. He uses both the four- and two-seam varieties of the fastball with good movement and plus command, according to scouting reports as well as the limited footage available. His breaker has earned a slider label, though the velocity and trajectory of the pitch suggest a curve; semantics aside, his high-frequency usage of the pitch adds to the workload-related concerns with respect to his health. The best pitch in Tanaka's arsenal is probably the splitter, which features arm-side run in addition to the trademark drop, and the fastball arm action adds to the deception of the split.

So we have the stuff and we have the stats, but what about the mechanics? Does Tanaka's delivery support the numbers, and can we glean anything through observation that isn’t apparent in statistical translations? As it turns out, the results are a mixed bag.

Mechanics Report Card









Release Distance




For an explanation of the grading system for pitching mechanics, please consult this pair of articles.

The first thing that stands out about Tanaka's delivery is that he employs the traditional NPB pause when pitching from the windup, stopping at the top of his delivery before engaging the second gear of his momentum. The pause might do well for deception, but it can also wreak havoc on a pitcher's consistency of mechanical timing. Tanaka earned an “N/A” for his repetition grade due to the lack of footage available, but the various pause patterns erect an obstacle in the path of repetition, which is compounded by the fact that he eliminates the pause when throwing from the stretch. He did minimize the pause in 2013, going with a lesser stall than in years past, which bodes well for his ability to make adjustments.

Tanaka also features a heavy drop-and-drive as he engages his secondary burst toward the plate, collapsing the back leg as he lowers his center of gravity. The strategy disrupts his balance (which is solid during the first gear of his motion), further complicating his attempts to repeat. On the plus side, Tanaka's second gear involves strong momentum that helps to extend his stride and improve his overall grade in that category. The net result of his poor initial move and late burst is a slightly above-average grade, but the right-hander has plenty of room to improve by eliminating the pause. For inspiration, he might look to countryman Yu Darvish, who began pitching from the stretch at all times in order to hone his mechanical timing.

The plus torque that Tanaka generates is all in the hips, with a strong delay of trunk rotation after foot strike that allows the hips to create separation before the shoulders fire. The available footage indicates that he does a good job of repeating the timing and sequencing of this portion of the delivery despite the inconsistent momentum.

Tanaka’s lateral balance falls off the map after foot strike, with some spine-tilt once his rotational phase kicks in. The end result is inconsistent posture at release point that drifts from average to very poor, and though his degree of spine-tilt is not tied to any particular pitch type, there has been a large discrepancy in his posture over time. Tanaka displayed better posture a few years ago, but his head drifted further off-track during the 2013 WBC, and the trend continued into the 2013 season. By the time Tanaka was pitching in the Japan Series in November, his posture had deteriorated to minus levels.

Tanaka does the little things well, such as maintaining a stable glove position and showing an ability to track toward the target after foot strike, but the combination of inconsistent momentum, wavering balance, and drifting posture is a bad omen for Tanaka's chances of sustaining the walk rates that have distinguished his statistical record in Japan. He has demonstrated the capacity to overcome these obstacles in the past, but because of his mechanical inconsistencies, he might very well struggle to find the same success and make adjustments against patient, powerful major-league hitters.


I expect that Tanaka will be successful on his first run through the league, but that he might face a daunting challenge as teams get multiple looks at his arsenal. Past footage indicates that the poor posture that marked his 2013 campaign was noticeably worse than what he had shown in previous seasons, and he may have to adjust his approach to find an optimal trade-off between the steeper trajectory afforded by an over-the-top motion and the consistency that can be found by harnessing his balance and posture. Tanaka's success may also be influenced by the coaching that he receives at the major-league level.

Tanaka lacks Darvish-level upside regardless of the contract that may be coming. That said, the new posting rules, combined with the shallow free agent market could make the team that wins the Tanaka sweepstakes—as opposed to bidding on the likes of current free agents Ervin Santana, Matt Garza, and Ubaldo Jimenez—happy. Tanaka might earn more than Darvish without being the Rangers ace’s equal, yet still be a solid investment for the team that secures his services.

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Doug, thanks for the brilliant explanation (as usual) of what could be difficult-to-understand subject matter.

Regarding Tanaka, you've curbed my enthusiasm a bit. Somebody is going to give him a lot of years, seeing as how they have paid a $20 million upfront cost already. Would it be fair to say that without mechanical adjustments, he is at a high risk of significant v-loss down the line?
I think that is a very fair statement. Pitchers with excessive spine tilt tend to drop velocity more rapidly ( ), and his heavy workloads add to the toll that has already taken place on his right arm.

That said, Tanaka has reportedly gained a little bit of velocity over the last few seasons, and he appears to have a stronger build now than in previous years, so he might be able to help stave off the velo drop with proper conditioning.
As always, this was awesome. Thanks for the continued output of ultra-educational material.
You're very welcome, Brad. Glad you enjoyed it!
Very cool! Great stuff!
That workload is frightening. Big risk with whomever gives him the inevitable long-term contract. Won't be drafting him in my dynasty league...
I was thinking the same thing for my keeper leagues, and I'm gonna let someone else pay the price of hype.
Great article! What are MLB scout(s) grading out Tanaka's pitch repertoire?

Good question, and one that the Professor could answer with much better accuracy. I believe that his fastball is considered a plus pitch and the split earns the highest grades, though he throws the breaking ball with a higher frequency (above 25%) than the splitter.
Might the higher usage at a younger age actually have helped him develop a stronger arm along with the potential for increased injury risk? He seems to use his lower half more than most US pitchers I see which may help him keep up with his past usage pattern. Do we see US coaches try to change the usage patterns of foreign pitchers when they get their hands on them? I'm curious if it is something the pitchers consider when seeking their new address.
You raise an interesting point, especially given the double-edged sword that exists with pitch-count restrictions - that is, such limitations simultaneously shield pitchers from over-use while preventing them from building the strength and stamina necessary to endure heavier workloads.

That said, I fear that Tanaka has gone too far in the other direction. In other words, while I do favor heavier patterns of building workloads, Tanaka provides a relatively extreme test case, such that I view his workloads as more of a negative than a positive in terms of his long-term projection. Combine this element with the higher frequency of outings (every five days rather than his typical seven, as pft1957 mentioned below) as well as the weakening posture, and it paints a pessimistic picture of his progression moving forward.

(note: above alliteration was incidental)

Because of this, US coaches naturally have to alter the usage patterns of NPB pitchers when they come aboard in order to fit into the rigid system of 5-day cycles. Not every pitcher will have the same experience of adjustment, so we will have to wait and see how Tanaka responds to the different demands of MLB.
The dead ball of 2011-2012 was less dead in 2013 but still deader than the pre-2011 ball with ERA's down 0.5 in 2013 as opposed to being down almost 1.0 in 2011-2012 and HR rates only 75% of pre-2011 levels after being almost 50% down in 2011-2012.

What strikes me most of Tanakas stats is the drop in his K/9 from 9.6 in 2011, 8.8 in 2012 and 7.8 in 2013. Either his velocity is down or he changed his approach, either way, I imagine teams would want to know since it suggests that his heavy workload in the past is taking its toll.

Anyways, a 90-92 mph two seamer strikes me as pretty average. The key is how much he loses off the fastball as a result of pitching every 5 days instead of every 7 days.
Great article. I was struck, like others by the myriad of red flags here. There's a bit of an unknown element with Japanese players and I think that perhaps includes some upside but between the lack of periphial stats, including decreased K/9, middling velocity and scary posture/injury history and reliance on his slider, I feel that if the bidding reaches the 5 years/90 million+20 posting, it will be a disaster for someone...

Not a 'sweepstakes' I want my team to win...
There is definitely an element of the unknown here, and in fact I am rooting for Tanaka to make me look bad and be a stud in the majors, because it is always more interesting to be pleasantly surprised. It's like Barney Stinson's One Rule - newer is always better.

But I share your caution, and I have a feeling that he is going to make a ton of money with a very questionable profile. But man, that splitter is insane - it looks kinda like Tim Hudson's, and Huddy rode that pitch to a mighty fine career.
Very interesting and informative, thanks.

I'm wondering how the number of red flags Tanaka has (and their severity) compares to most established starting MLB pitchers? Are there any pitchers with perfect mechanics?
There isn't a pitcher in the modern game with perfect mechanics, but there are some that have plus grades in every category - in fact, some of the prospects that I have recently covered fall into that category, including Zimmer and Taillon, while Syndergaard and Stephenson each fell one category short of plus across the board.

Tanaka's delivery is merely average overall, maybe a C or C+ grade on the MLB scale (with an upshot of a B- if his repetition is amazing).
Thanks for the excellent report Doug! I’d been eagerly anticipating this one.

I forget where now, but I remember reading an article several months ago before 'Tanaka Mania' that expressed similar concerns. I have a big soft spot for Japanese pitchers, but that’s primarily fueled by Darvish, who is very much not in the mold of the traditional Japanese pitcher, and I enjoy baseball people’s minds exploding. Tanaka could be good, but he’s certainly no Darvish.

Speaking of which, I've been really surprised by comments I've seen from some scouts opining that Tanaka COULD actually be as good (or better than!) Darvish. Sure, that splitter is nasty, but his ceiling seems to be Kuroda, maybe with a slightly higher strikeout rate. Their velocity is almost identical ( and neither has the jaw-dropping arsenal of Darvish. A slightly better Kuroda is nothing to sneeze at, but that’s assuming everything goes right.

Doug noting that Tanaka’s mechanics are actually somewhat poor only adds fuel to the fire. (Darvish’s walk rate increased dramatically when he came over, and for comparison, here's Doug's article on him back then: Couple that with MLB’s smaller strike zone and significantly more power and... yikes. I wouldn’t be surprised if Tanaka’s reputation helped earn him a few more strikes still. I’ve really enjoyed following his story long before he was on America’s radar and very much hope he succeeds, but if I were running a team I certainly wouldn’t be fighting for the chance to risk 20M per on him.

Doug, while I have your attention - how would you compare Darvish's mechanics now from when he first came over? He's obviously made some changes and we've all seen the crazy GIF that suggests he’s improved dramatically in the repetition department. I’ve really enjoyed watching him improve and blow guys away. Darvish is actually the reason why I bought an subscription in 2013! Blasted almost-perfect game...

- Jon
Thanks for the kind words, Jon, and I appreciate the compare/contrast to what I said about Darvish in the past. I was much higher on Darvish when he came over, even with the expected adjustment period, but I am not so sanguine on Tanka's odds for high-level success.

Darvish has made some outstanding improvements in his two years in MLB. Most notably, he ditched the windup in order to find more consistency and repetition, with outstanding results. He has simplified his delivery to focus on the elements that he does so well - including plus momentum, excellent balance, and perfect posture. Once he honed the timing element, it was downright scary.

For some background on his progression, I wrote about his late-2012 improvements here:

I also detailed his unique combo of momentum and posture with respect to release distance, with a nod to his constant stretch of 2013, here:

And also mentioned his windup-stretch patterns here (June 2013):

If Tanaka is able to make similarly impactful adjustments, then he could very well find major success in the bigs. But his upside state-side likely hinges on his ability to make major changes without losing effectiveness.
Awesome, thanks Doug! I definitely need to catch on your more recent articles (alas, audio tends to be a better fit when in the car and doing yard work). I do recall listening to the podcast and you mentioning that Darvish's permanent transition from the windup to the stretch was a huge help, but I figured there was even more to dig into. Seems I have a bit of homework of my own to complete now!

Speaking of the podcast, let me also offer my thanks for your super-detailed reply to my question about pitching in Colorado back in episode #14. I'm obviously completely biased, but that was probably my favorite segment you guys have ever done.

There’s plenty of good discussion on the Internet about the ‘WHAT’s of pitching, but rarely are the ‘WHY’s covered, especially in the context of extreme ballparks. Your in-depth explanation of the accumulating deleterious effects of playing at altitude makes total sense, and I’m totally on board with your argument that the change-up should be THE pitch you build around when dealing with a huge ballpark and thin, dry air.

I understand the theory behind Paul preferring sinkerballers in that environment, but when there’s so much grass to cover your goal really needs to be keeping the ball out of play any way you can. Home runs kill you, but singles add up over time too.

Anyways, I’ll try not to derail this article’s comments thread any further. Eagerly awaiting the next episode of TINSTAAPP, so consider this a gentle prodding!

- Jon