One of Tatsuya Imai’s pitches, in particular, is getting rave reviews at Astros spring training

There are plenty of under-the-radar X-factors who could turn the Houston Astros' 2026 season for better or worse, but no player figures to have a greater impact on their fortunes than Tatsuya Imai. The 27-year-old Japanese star will enter the season with immense pressure to perform, given both the hype and the risk the Astros have taken in investing in him.

It was easy to be down on Imai before he even picked up a baseball this year. Seeing the right-hander settle for a three-year deal worth up to $63 million after offseason projections regularly had him topping $150 million, with some going as high as $190 million, makes you wonder. Did the rest of the league know something that Houston didn't?

We're nowhere close to answering that question, but Imai has finally thrown a baseball for Houston, and the reports from his first bullpen session, specifically the impression his splitter left on his teammates, are astounding.

Tatsuya Imai's splitter is drawing immense praise from his Astros teammates

The scouting report for Imai includes a high-octane fastball that can reach the upper 90s, a devastating slider, and a plethora of other junk that he can toss up there to confound hitters. Except for the fastball velocity, most of that sounds like standard fare for a Japanese hurler. Typically, these stars come over with a laundry list of pitches in their arsenal, with misdirection and confusion being the name of the game.

There's another hallmark of a Japanese pitcher that has become commonplace. That's the usage of a splitter. While not exclusive to this cohort, many of the best splitters in the game are owned by starters who began their careers in Japan.

Still, for Imai, this pitch wasn't talked about as often as a reason he could be successful, as his fastball and slider were. Now, after his first bullpen session, folks are starting to realize that it could be a real weapon.

Imai threw 17 pitches and faced five batters, beginning with Jose Altuve before facing Carlos Correa, Jake Meyers, and Taylor Trammel, with the latter three all going down via the strikeout.

“Be honest with you, I played this game for 24 years now and 11 professionally, and I’ve never seen a pitch like that before in my life,” Trammel said while discussing Imai's splitter.

“It comes out hard, and when it’s time to make a decision, it just drops down,” Correa said. “[Dodgers pitcher Yoshinobu] Yamamoto has the same thing, where he throws a fastball down and tries to make you chase the split. He can do special things like that, also.”

“The ball when he’s coming downhill, he releases it in his hand, and it’s almost like a snap,” Trammell added. “Everything was lively. I thought all of his pitches I saw for the most part. The fastball is very hoppy. It’s got a little bit of run to it. And then, I mean, we saw that splitter.”

That's some high praise. Any and all comparisons to Yoshinobu Yamamoto are more than welcome. Most importantly, it seems that, although the splitter itself is nasty, the way it plays off his fastball has the potential to make it even more lethal.

It's the type of pitch that makes you think it could be even more effective in the MLB than it was in Japan's NPB. NPB hitters are more contact-oriented, and the pitchers typically possess lower fastball velocities than their MLB counterparts. Therefore, they're used to spoiling those sorts of diving splits without having to fear top-end velocity. However, big league hitters are faced with near-triple-digit heaters on the regular and typically sell out for power. That tunneling effect with the fastball then could be even more impactful here.

Altuve didn't see the splitter. He saw just two pitches before grounding out, the first being a slider that generated a whiff.

“He threw me a slider that [you] couldn’t really see the spin. Nice and sharp. And then after that, a fastball. I saw two pitches. So, yeah, very good. Obviously, two pitches is not enough, I wish I could get more. But the first impression is really good. He’s going to help this team a lot," Altuve said.

We'll need to see more before we're fully confident that he'll be a star for Houston, but color us intrigued.