The Offseason Monitor: Imai to the Astros
A quick look at what to expect from Tatsuya Imai in 2026
The Astros really needed help in their rotation entering this offseason, and they’ve made two moves to get some. First, they traded for Mike Burrows. And now they’ve signed the best SP in the international market, Tatsuya Imai.
I’m not the best resource for learning about international players, but I’ll compile some information for you here.
2025 Stats
163 IP
1.92 ERA
0.89 WHIP
27.8% K%
7.0% BB%
0.33 HR/9
He was very good over there. And that got him a three-year, $54 million deal in Houston. $18 million a year is a pretty nice salary if you’re asking me. But it doesn’t compare with the big names. Yamamoto got a ridiculous $27 million per year for a ridiculous 12 years. He was a couple of years younger than Imai, but the dollar figures alone tell you that expectations should be tempered.
His pitch mix (I took it from this article):
He has the splitter, but it’s a lot lower usage than you typically see from a Japanese pitcher. The fastball velo is also not great, at least not over here in North America. It’s a different brand of baseball in Japan. Having just 95 in the bag without a dominant splitter (I guess I don’t know it’s not dominant, but at 4% usage, it must not be all that great) tells you a lot right away. There aren’t too many MLB aces with this sort of pitch mix.
That isn’t to say he can’t be quite good. It would just seem like we’re looking at a big league SP3-SP4 rather than an SP1 like Yamamoto.
So I took my best guess inputs and slapped ‘em into the projection model, and here’s what we come up with:
→ 29 GS, 159 IP, 3.91 ERA, 1.21 WHIP, 24.5% K%, 8.0% BB%
That puts him around guys like Sandy Alcantara and Tanner Bibee in projection-derived roto value. And from what I’ve read, that sounds right to me!
He is, absolutely, a standard league fantasy pitcher with that. And you have to say he has more upside than Alcantara and Bibee just because there is more “unknown”. Maybe the Astros will tweak him, maybe they already have some ideas about how to improve him. Maybe the splitter will be more of a weapon in the MLB since it’s such an effective tool over here for the guys that can throw it.
The reverse is true as well. There’s more downside for the same reasons. Maybe 95mph just isn’t good enough with the command and secondaries he has. Only time will tell. But the less information we have, the wider the range of potential outcomes.
So that’s about where I’d be taking him - around the time that the Alcantaras, Gallens, and Bibees of the world start going.
Steamer is the only other system with a projection on him, and it’s from before the signing with the Astros was announced. So this would be a neutral park projection:
→ 148 IP, 4.29 ERA, 1.38 WHIP, 130 SO, 21.6% K%, 9.3% BB%
Harsh, bro!
In real life, it’s hard to complain about the signing. It’s not a franchise-altering amount of money to spend, so even if he turns out to be more of an SP4 than an SP1, I don’t think the Astros will be kicking themselves too much about it.