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Breaking Down Offseason Targets - Yoshinobu Yamamoto

My favorite pitching target this offseason.

World Baseball Classic Semifinals: Mexico v Japan Photo by Eric Espada/Getty Images

I’ve already broken down the top 3 American pitching targets - Blake Snell, Sonny Gray, and Aaron Nola - so now it’s time to turn my attention to the Japanese arms, the best of which is Yoshinobu Yamamoto. And I’ll spare you the suspense - Yamamoto is my favorite pitching target this offseason.

That’s also connected to why Sonny Gray is my favorite American pitching target.

Think about it this way. If the St. Louis Cardinals sign Aaron Nola, they almost certainly won’t shell out the $200+ million that it will likely take to secure Yamamoto’s services. The same is probably true of Blake Snell, though it’s tough to predict what kind of a contract he will get. And I want Yamamoto. If the Cardinals sign Sonny Gray early in the offseason, they aren’t necessarily out of the Yamamoto bidding.

I also don’t want the Cardinals signing two pitchers with the qualifying offer as they shouldn’t mortgage 2 of their top 3 picks in a year when the Cardinals will have the highest pick they’ve had in a long time.

So, for me, it makes sense to nab the top Japanese arm, and maybe even the top overall arm, on the market and pair him with a quality #2 in Sonny Gray.

So now that I’ve given you the punchline up front, lets get into why Yamamoto is my favorite target and why he may just be the top arm in free agency this year.


There’s really not much I can add to Yamamoto’s Baseball Reference page. I mean, from his age 18 to 24 seasons, the guy put up a 1.72 ERA. It’s hard to do more than that.

This past season, that figure was 1.16 and he paired that with a 26.7% strikeout rate and a 4.2% walk rate. Oh, and he gave up just 2 home runs all season. In 171 innings pitched.

I want to put those last few numbers in perspective, though, because baseball is different in Japan. It tends to be more contact heavy and less power oriented. The average strikeout rate for the Japanese Pacific League (the league that Yamamoto played in) was 19.3%, which is a few ticks lower than the 22.7% league average strikeout rate in Major League Baseball this year. So while Yamamoto’s strikeout rate was impressive in and of itself, it was especially impressive when you consider the offensive environment of the league that he pitched in.

The average walk rate of the two leagues was actually pretty similar this year with the Japanese Pacific League just a hair lower (8.0%) than the majors (8.6%). The big difference is in home runs. In the majors this year, the league average HR/9 was 1.23 while that figure was just 0.77 in Japan.

So, while Yamamoto’s home run figure is impressive, it’s likely deflated by the offensive environment in Japan. These are all important things to consider but I also want to look at how Yamamoto compares to some previous Japanese pitchers that have made the jump to the majors.

We’ll just look at each pitcher’s final full Japanese season for now. (That means I pulled Ohtani’s 2016 stats instead of his 2017 stats in which he threw only 26 innings.)

Yamamoto Compared to Other NPB Pitchers

Player Year Age ERA K% BB% HR/9
Player Year Age ERA K% BB% HR/9
Yoshinobu Yamamoto 2023 24 1.16 26.7 4.2 0.1
Kodai Senga 2022 29 1.89 27.4 8.6 0.4
Shohei Ohtani 2016 21 1.86 31.2 8.2 0.3
Kenta Maeda 2015 27 2.09 21.3 5.0 0.2
Masahiro Tanaka 2013 24 1.27 22.3 3.9 0.3
Yu Darvish 2011 24 1.44 31.2 4.1 0.2

All of these pitchers have had successful MLB careers, to different extents, but none of them were able to match Yamamoto’s ERA in his final NPB season and only Tanaka and Darvish walked batters at a lower rate, and only just barely.

Tanaka settled in with a 4.8% walk rate in his MLB career while Darvish is a bit higher, though still below the MLB average, at 7.8%. The most comparable player on this list in terms of strikeout rate is Kodai Senga and he’s coming off a season in which he finished with a 29.1% strikeout rate and 3.4 fWAR. Keep in mind, though, that Senga was 30 this year in his first major league season and Yamamoto will be 25.

Considering that and the success of the players on the list, I’m really not too worried about Yamamoto’s game translating to the majors. That’s part of why I like him so much. The other part is that he’s so young. If the Cardinals are going to give out a long-term contract to a pitcher, which always incurs a lot of risk, I would prefer they give out that contract to the soon-to-be 25-year-old Yamamoto as opposed to the soon-to-be 31-year-old Aaron Nola.

It’s time for another table now, and this one shows the first year MLB stats of the players in the previous table to get an idea for how well their game translated immediately after making the jump.

First Year MLB stats of Selected NPB pitchers

Player Year FIP K% BB% fWAR
Player Year FIP K% BB% fWAR
Kodai Senga 2023 3.63 29.1 11.1 3.4
Shohei Ohtani 2018 3.57 29.9 10.4 1.1
Kenta Maeda 2016 3.58 25.0 7.0 2.9
Masahiro Tanaka 2014 3.04 26.0 3.9 2.9
Yu Darvish 2012 3.29 27.1 10.9 4.7

There is not a single player on this list that busted. Shohei Ohtani’s fWAR was kept down from only throwing 51.2 innings but there’s no one that would argue against his career as a whole. Beyond that, the lowest fWARs are from Tanaka and Maeda and Tanaka’s was also kept down from a low innings pitched total (136.1) while Yamamoto is simply a much higher profile player than Maeda.

Assuming that Yamamoto’s game translates as well as the player’s listed above, it seems like the floor for him would be 3 fWAR. That’s a really strong floor.

Things aren’t that simple so we can’t say that as a matter of fact but the point is that Yamamoto is in good company, and, generally, higher profile Japanese arms tend to have MLB success. Throw in Yamamoto’s combination of stuff and control and then factor in his youth and it’s pretty clear to me that he should be the top target among free agent pitchers this offseason.

If there’s one area of concern it’s with workload. Japanese pitchers throw once every week, not once every 5 days. According to Baseball Reference, Yamamoto is also 5’10” and 176 pounds. That probably adds a little extra durability risk to a pitcher who will also be throwing more often than he ever has.

That’s a legitimate concern.

I would counter by adding that the impact of the workload change is probably a bit overblown and, while it matters, Japanese pitchers tend to adjust pretty well. And while there’s not a huge track record for pitchers of Yamamoto’s size holding up to a starter’s workload in the majors, it’s worth mentioning that Yamamoto has stayed remarkably healthy in his career thus far.

In fact, he threw 171 innings this year after throwing 193 in 2022, 193.2 in 2021, and even 126.2 in 2020, a year interrupted by COVID. That doesn’t mean he won’t get injured or that his durability won’t change; it simply means that he has a history of staying healthy and making his starts.

When researching Yamamoto I also came across an interesting comment about the pitcher in an article from MLB Trade Rumors:

The right-hander is known for his unique training style, with a focus on flexibility and mobility as well as using javelin-like and hammer-like tools. He also has a personal chef/nutritionist to manage his diet.

There’s always some element of luck involved with staying healthy, but Yamamoto appears to be someone with a good idea of how to prepare his body to handle the stress of pitching and the dedication to keep his body in top pitching shape.

That’s another point in his favor.

So, really, for me, the main concern with Yamamoto is durability. If something is going to make his contract a bust, it’s likely injuries and not poor performance. With that said, I’m not overly concerned about his durability, any more than I would be with a pitcher on the wrong side of 30 seeking a big contract. So, the potential durability concerns are something to be aware of, but they shouldn’t scare off suitors like the Cardinals.


Now that I’ve covered Yamamoto from a statistical standpoint and put his numbers in perspective to those of other Japanese pitchers, I want to dive into his arsenal.

I’ll be honest - I haven’t seen Yamamoto pitch a whole lot and I don’t have a lot of data on his pitches. That’s why this section will be shorter than usual.

That doesn’t mean I have nothing to offer, though.

Yamamoto pitched in two World Baseball Classic games prior to the start of the MLB season and I have his stuff+ numbers from the one start that he made. Keep in mind that we’re dealing with a small sample size here, but the information can help us get a grasp on just how good Yamamoto truly is.

Yamamoto WBC Stuff+ By Pitch

Pitch # Pitches Thrown Stuff+ Location+ Pitching+
Pitch # Pitches Thrown Stuff+ Location+ Pitching+
Curveball 11 122.3 111.4 123.5
Four-Seam Fastball 30 121.3 114.9 123.4
Changeup 15 110.7 98 108.2
Cutter 4 105.9 109.9 102.1

There are a whole lot of caveats with this data but I’ll start by saying that, as a whole, Yamamoto had a 117.8 stuff+ in his lone World Baseball Classic start. That’s really good.

But onto the caveats.

For starters, the stuff+ data, provided by Eno Sarris, has Yamamoto throwing a changeup but that “changeup” is really a splitter that is Yamamoto’s go-to secondary. The pitch sits in the low-90s, which is hard for a splitter/changeup, and while normally I would be concerned about an offspeed pitch with so little velocity difference from the fastball, Yamamoto’s splitter seems to move enough to make it a really good pitch.

The second caveat I have is that stuff+ is basically irrelevant for changeups and is often inconsistent or downright bad at grading them. That’s really because it’s how a changeup plays off the fastball that matters most, as that’s kind of the point of a changeup, as opposed to the physical characteristics of the pitch itself. Splitters aren’t exactly the same thing as changeups but they are close enough to be considered similarly.

So, while Yamamoto’s “changeup” graded out well, that doesn’t really matter. That’s not to say it isn’t a good pitch (because it is), it’s just to say that the number itself isn’t really important.

Thirdly, the stuff+ data refers to a cutter but it’s unclear to me whether he throws a cutter, a slider, or both. Those two pitches have some overlapping characteristics and Yamamoto is supposedly able to tweak his pitch shapes so that makes it hard to tell what he’s actually throwing at times. So, basically, we know that he has one cutterish/sliderish pitch and maybe two.

For the rest of this section, I’m going to rely on Baseball America’s scouting report of Yamamoto to give us information about his stuff.

According to Baseball America, the right-hander’s fastball sits 93-96, but I’ve seen that it’s been as high as 99 before, and has great riding life. There are contrasting reports from Fangraphs and Baseball America on whether it runs or cuts so I’ll have to wait for the movement data to make a determination on that.

Still, a mid-90s fastball with riding life and good command seems like a pretty good pitch to me.

BA rates the splitter as “plus-plus” with “huge depth” and it’s the latter part of that which eases my concern with hard offspeed pitches. A hard offspeed pitch without much movement difference from the fastball tends not to perform well but a hard offspeed pitch with a lot of movement difference from the fastball tends to perform really well. That makes sense, though. Basically the idea is that the pitch looks the same and then falls off the table.

Baseball America also credits Yamamoto with 3 other pitches - a curveball, a slider, and a cutter - which all grade out as above average to plus. That confirms the idea that his slider and cutter are separate pitches, which is helpful for us. I should also mention that they are both thrown less than Yamamoto’s curveball.

Fangraphs and Baseball America both agree that Yamamoto has clean mechanics and a lot of athleticism on the mound (which meshes with the video I’ve seen of Yamamoto), and that makes me feel better about Yamamoto’s durability long term.

The final thing to add is that Yamamoto reportedly commands his secondaries almost as well as his fastball which gives him a nasty, deep, and well commanded arsenal and that is a beautiful combination.

From what I’ve read and what I’ve seen I don’t really have any concerns about Yamamoto’s stuff translating to the majors. Pitchers of his caliber tend to play well in the majors and he brings a rare combination of stuff, command, and youth that really makes him stand out, even from among the talented Japanese pitchers that have come to the majors in the last decade.


I said it at the beginning of this article and I’ll say it again here - Yamamoto is my favorite pitching target this offseason and I would love to see the Cardinals pair him with Sonny Gray.

The main issue facing the team is not only cost but also the interest from the rest of the league. Yamamoto will likely reach or even eclipse $200 million in total contract value and that’s not even including the posting fee, which would likely go beyond $25 million.

That’s a hefty price to pay. Then there’s the fact that Yamamoto may have a preference on where he plays. That may prove to be more valuable to him than an extra couple of million dollars. Only he knows what his preferences are, if he has any, but with most of the pitching needy teams interested in Yamamoto, the Cardinals will face steep competition for him and may not be able to satisfy any conditions that he may have,

That’s all speculative for now, though.

Yamamoto is an extremely talented arm and whoever signs him will be signing him for his prime years. With a history of top Japanese arms performing well in the majors and Yamamoto’s combination of durability, age, stuff, and command, there is no better arm on the market.

On Tuesday, I’ll be back with a look at the next best Japanese pitcher on the market - Shota Imanaga.

Thanks for reading, VEB. Have a fantastic Sunday.