Tommy John for Tazawa

Greetings Fangraphians. I have awakened from my six-week Fangraphs slumber to bring you… analysis of Junichi Tazawa’s surgery.

Last month, the Red Sox learned that Tommy John surgery would knock their #3 prospect out of commission for the next 12 months or so. Let’s take a look back at how they got here.

Tazawa signed with Boston in November 2008, after a four-year career with Shin-Nihon Oil Eneos of Japan’s Industrial Leagues. The Industrial Leagues are comprised of amateur teams fielded by Japan’s corporations, such as Toyota and Yamaha. I’m sure someone will ask how the Industrial League compares to the American minors in terms of talent, but to me it’s an apples and oranges situation in that the Industrial Leagues have a mix of NPB draft prospect talent, and guys with corporate jobs who happen to play baseball. That said, I’d say the better Industrial League teams probably grade somewhere around Indy Leauge ball.

I was probably more impressed than most to see Tazawa reach the Bigs last season. Based on the observation that it usually takes younger Industrial League pitchers at least a year or two of pro seasoning before they begin to perform at the top level in Japan, I expected Tazawa to hit a wall at some point his first pro season. Here’s a quote from an article I wrote last February:

[…] In America, he will have to adjust to the reality that even in 2A there will be guys capable of hitting his best stuff. This will challenge him to improve on his approach on the mound and preparation for the game.

It turned out that 2A wasn’t a huge challenge for Tazawa, and he did well in two 3A starts before finding the wall I envisioned at the MLB level. The Industrial Leauges are a long way from the pennant race in AL East, and that got that far in 10 months was quite an achievement.

So hindsight being 20/20, was he rushed?

In the post I referenced above, I also made a note about the mileage on Tazawa’s arm coming into the Red Sox contract:

Looking at last year’s Intercity Championship, which Tazawa’s Eneos won, Tazawa started on Sept 1, Sept 4, pitched relief on Sept 6, started again on Sept 8, and finally closed out the tourney with two innings on Sept 9. That was a total of 28.1 innings in nine days, with no more than three days rest in between apparances. I don’t have pitch count data, but I recall reading that he had gotten around 150 in one game last year* (not sure if it was this tournament or another one). And he did wear out down the stretch — in his last appearance he didn’t allow any runs, but was nicked for 7 hits in 2 innings.The upside here is that the Red Sox certainly won’t put this kind of strain on Tazawa’s arm. He’ll be put under pitch counts and watched carefully. The adjustment he’ll have to make is pitching on a regular, routine basis, instead of the short, extreme bursts of activity with long breaks in between.

* In researching today’s post, I found an article that said he had thrown 158 pitches in the September 4, 2008 game.

One thing I didn’t foresee was that Boston have him pitch from the windup. Tazawa always worked from the stretch in Japan, probably because he spent most of his Industrial League career as a reliever. His workload also increased from 103 Industrial League innings to 134.2 across three levels in the States.

So was he rushed? I have the sense that injury problems were to some extent inevitable, but yeah, it does feel like the Red Sox were aggressive with him.

We hoped you liked reading Tommy John for Tazawa by Patrick Newman!

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Patrick Newman is a veteran enthusiast of Japanese baseball who happens to write about it at, and on Twitter @npbtracker.

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I strongly disagree with idea that the Red Sox mishandled him. To an extend an argument can be made that they should have used him less but they can be said about any pitcher that gets injured. A workload increase of approximately 30% for a pitcher his age is a relatively standard. If he was drafted like a domestic college pitcher leaving after his junior year, he would have been treated the same. To make clear Tawaza (23) is two full years old then the average college junior last year. He would should have and was treated the same way as everyone else. For example: Kyle Weiland he reliever/started in college, his innings the two previous years 90.1 (Lowell/Notre Dame) and 132.2 (Salem). Pitching is general is violent on the human body and to minimize stress on Tazawa’s arm they introduced the wind up. This injury is more of result of his pitching in Japan from the stretch and abusive number of pitches allowed to be thrown. The Red Sox handled him with care but ultimately his previous years in Japan undermined there goals.


The article is more saying that the Sox were aggressive with him in terms of time to the majors than with his workload.


103 innings of industrial league ball is more like 60 ip in majors/high minors.