In Japanese, a fastball is called a “straight”, a running fastball a “shoot” and with the exception of a cutter or a two-seam fastball, which are oddly enough called cutters and two-seamers, all other pitches are labeled breaking balls.

Way to Tsutsugo

Of course, pitchers call their deliveries what they will, whether or not the pitches actually behave like others with the same name. When researching Yoshitomo Tsutsugo after he declared his desire to play in the big leagues, it was pointed out to me that he had trouble with fastballs.

There is anecdotal evidence of scouts, who report what they see in limited samples, and now there is pitch tracking data, although that is proprietary and only available to the clubs. Delta Graphs, following in the footsteps of Fan Graphs, has pitch value ratings for hitters effectiveness versus different pitch types.

I’ve combed through the Delta Graph data for players with 300-plus plate appearances since 2014, and compared each of those batters to how much better or worse they are against fastballs, curves and sliders than the average of these regulars.

Frankly, Tsutsugo had a relatively poor 2019 against fastballs, 1.12 runs above the NPB average per 100 fastballs. This ranked him 33rd among the 89 hitters with 300 PAs in NPB in 2019.

The average of regulars relative to the NPB norm since 2014 has been 0.63 runs per 100 fastballs, and Tsutsugo’s 1.12 runs in 2019 was 0.37 standard deviations above that mean. For him it was a terrible year. Since 2014, he’s averaged being 0.90 standard deviations above the mean for NPB regulars. That ranks him 10th in NPB among current players with three years of regular service during that stretch.

Without further adieu, here are the best (according to Delta Graphs) fastball hitters in Japanese baseball based on the unweighted average of how many standard deviations they are above the mean in each 300-PA season since 2018. The one hitter who is head and shoulders above the rest will never make it to MLB following Yuki Yanagita‘s announcement this past week that he will forgo free agency in lieu of a seven-year contract with the SoftBank Hawks.

Japan’s best fastball hitters (3-plus seasons as regulars)

Honorable mentions

If we only include players with two years as regulars, Neftali Soto of the BayStars would rank second (1.78) and Masataka Yoshida of the Buffaloes would be third (1.56).

Of course, there are two big differences between NPB and MLB in terms of the quality of fastballs. These are:

1. While the tackier NPB ball is easier to spin, it doesn’t appear to run as much — giving less horizontal movement on fastballs, two-seamers, splitters and straight changes.
2. The average velocity one sees in NPB is a few ticks lower than in MLB for several reasons. Japan imports virtually no international amateur talent, weight training is only beginning to take hold, and the year-round throwing practice and the necessities of pitching game after game in tournament play wipe out many of the nation’s best pitchers before they finish junior high school.

Because of those differences, one expects players — especially those in their prime or past it, to face serious adjustment issues in MLB.