Anatomy of a player: Hiroki Kuroda

Japanese pitchers are known for their ability to chug champagne. (Icon/SMI)

Hiroki Kuroda was kind of an afterthought last offseason after big splashes and some flops by Japanese players in recent years. He quietly signed a three-year, $35 million contract with the Dodgers with some nice perks including a moving allowance, English lessons and eight first-class tickets from L.A. to Japan each year (excellent work, Steve Hillard).

Kuroda was already 33 years old, so this move didn’t garner much national attention. Now, with Kuroda’s last start knocking off the Cubs in the NLDS, he is a hot topic in Los Angeles. Let’s look at Kuroda and how his stuff translated from his long career in Japan.

Kuroda in Japan

Hiroki Kuroda was drafted in the second round by the Hiroshima Toyo Carp in 1997. After a slow start in his first few years, Kuroda settled into a spot in the rotation and pitched very well. In 2006, he dominated the league, posting an ERA under two and walking just 21 in nearly 189 innings.

Despite his best efforts, the Carp never made the postseason during the 11 years he pitched for the team. Kuroda was known as a control pitcher who didn’t walk many batters and kept the ball in the park despite pitching in a homer-friendly park. After becoming a free agent after the 2007 season, he decided he wanted to pitch in America and choose the Dodgers over the Mariners (looking back, what a good choice he made).

Translating his performance in Japan

There were legitimate concerns from the moment he signed about how well Kuroda would pitch in the big leagues. Previous pitchers who had made the transition from Japan to MLB had seen a large spike in their walk rates. Kuroda needed to keep his walks down, as he wasn’t striking out enough batters to compensate. In his last year in Japan, he had a strikeout rate of 5.9 per nine innings, but a walk rate of just 2.0 per nine innings. That produced a solid three-to-one ratio, but if his walk rate increased he could be in some trouble even if he was able to keep his strikeout rate nearly the same.

It turned out that Kuroda had a fine year for the Dodgers, posting rates almost identical to his previous year in Japan (5.8 K/G and 2.1 BB/G). This was the key to his ERA of 3.73 and an even better FIP of 3.53. That is front line material and cheap for what the Dodgers were paying him. That is very solid production and it appears they can look forward to good production in the next two years as well.

Let’s look at his stuff to see how Kuroda got things done.

Kuroda’s stuff

Scouting reports were kind of hard to find on Kuroda but the ones I located appear to be mostly spot-on in their assessment. Kuroda throws a two-and four-seam fastball, a splitter and a slider that has been called a shuuto. Here is a look at his movement chart.


Kuroda throws his fastball and sinker at near 93 mph. This is a bit unusual, because most pitchers who throw both will throw their sinker slower than their four-seamer. Kuroda generally tries to keep his fastball on the outer half of the plate, so he throws his sinker more to left-handed batters; it has good movement away from them. His four-seamer goes more to right-handed batters, since it has little horizontal movement in to them.

Unlike other Japanese imports, Kuroda doesn’t seem to pitch backwards much. Many pitchers from Japan like to throw off-speed pitches in fastball counts and fastballs in off-speed counts, but Kuroda prefers his fastball on the first pitch and when he falls behind. He throws either his four-seamer or sinker more than 70 percent of the time 1-0, 2-0, 2-1 and 3-1. This may be a testament to his belief in his fastball, which is a very solid pitch with plus velocity. This conventional style of pitching may be the reason he didn’t see a spike in his walk rates this year. If so, this could be an important indicator of future success of other Japanese pitchers.

Kuroda’s best off-speed pitch is his splitter. It acts like a change-up, and Kuroda uses it more to left-handed batters, as you would expect. That said, the pitch mechanically works the opposite of a straight change-up. Generally, a straight change-up is thrown with the same spin as a fastball, but around 10 mph slower. The hitter is fooled because he sees the same spin, thinks fastball, and swings way too early for a ball thrown much more slowly. The “drop” you see from the straight change is produced by gravity, not the spin of the ball. Because the the ball is thrown more slowly, it is in the air long and gravity has more time to work its magic.

Kuroda’s splitter produces the downward movement with spin and not gravity. Kuroda throws his splitter at about 88 mph, so it is in the air for a shorter time than an 83 mph change-up would be. The downward movement comes from the spin and you can see the difference in vertical movement compared to his fastball. For comparison look at Tom Glavine‘s straight change. So here the batter sees a velocity that matches up with a fastball velocity but still swings over the pitch because of the lesser vertical movement. This will be an important pitch for Kuroda going against the Phillies in the NLCS, so keep an eye out for it.

The slider, or shuuto, Kuroda throws is a type of pitch I have talked about a lot before. It tends to be a harder slider without much horizontal movement away from right-handed batters. I am generally not a fan of a pitch like this because for a slider to be a truly effective strikeout pitch it needs to start on the outside corner and then move out of the zone, fooling the right-handed batter into swinging. Kuroda, however, has that ability in his slider.

You can see that it can be thrown with quite good horizontal move and even some vertical drop. Kuroda accomplishes this by adding or subtracting spin from the ball and previous scouting reports note this ability, so we can assume he has good control over this. If Kuroda wants to throw the slider for a strike, he can reduce the spin and keep the slider on the outside corner. If he wants to use it as a strikeout pitch, he can add spin and get the horizontal movement you see in good sliders. While Kuroda tends to hold back on the splitter until he is ahead in the count, he will throw his slider in any count. The ability to use this pitch as a get-me-over breaking ball and as a wicked strikeout pitch is a huge advantage for him.


While some other pitchers have struggled moving from Japan to America, Hiroki Kuroda has made a seamless transition. The fact that he throws more straightforwardly than most Japanese pitchers is likely a good reason why. With an above- average fastball (especially his sinker) and a very good splitter, he can keep the ball on the ground for the most part. While his slider can be thrown for strikes, he also can use it as a strikeout pitch. Kuroda should be effective going forward for the Dodgers and could be a key pitcher against the Phillies because of all their strong left-handed bats.

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