At long last, the wait is almost over. Japanese right-hander Roki Sasaki is set to make his regular-season MLB debut on Wednesday morning, taking the mound for the Los Angeles Dodgers in the finale of their two-game set against the Chicago Cubs in Tokyo.
Fans in the States have been looking forward to this moment for years now. Since 2019, when the righty’s 101-mph fastball broke Shohei Ohtani’s Japanese high school velocity record. Or since 2022, when he threw the NPB’s first perfect game in nearly three decades and tied a league record with 19 strikeouts in a start. Or since 2023, when he showed out on the world stage while helping Team Japan capture the World Baseball Classic.
Sasaki finally made the jump to the Majors this winter, landing with — who else? — the Dodgers in a bidding war that hijacked the offseasons of several different teams. Now we get to see what all the fuss is about, as 23-year-old will get his first taste of big-league competition in a game that actually counts.
Sasaki has been mostly as-advertised this spring, striking out seven while allowing just three hits over seven scoreless innings. But what should we expect in his first real start? Here’s a complete breakdown of what makes the right-hander so special, and where he still has some room for improvement.
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Roki Sasaki scouting report: Each pitch ranked worst to best
3) Slider
Granted, “worse” here is very much relative; Sasaki’s slider still earned a 40.7 percent whiff rate in Japan this past season. But it’s the pitch he throws least often, and its spin rate this spring would rank him down near the 1st percentile among all MLB breaking balls.
Most scouts rate it closer to above average than plus, which for Sasaki qualifies as a weakness. It’s also worth noting that, as with the righty’s other pitches, he saw a bit of regression in 2024, in both velocity (from the upper 80s down to 83-85) and whiff rate (48.6 percent in 2023). It’s not a bad pitch, but it lacks the biting movement or pinpoint command you’d like to see.
2) Fastball
We mentioned Sasaki’s velocity above, and it is indeed eye-popping: topping out at 102 mph in the past and averaging 98.8 mph 2023. Again, though, that backslid a bit in 2024, down to 96.8 — concerning enough that Sasaki asked prospective Major League teams to pitch him on how they might help him get that velocity back were he to sign with them.
It’s also worth noting that the pitch missed fewer bats last season, from 24 percent down to 13.1. Velocity was part of that equation, and movement was another: Sasaki’s fastball, for all its heat, tends to be pretty straight, without a ton of ride, run or cut. To be clear, we’re picking nits a bit here; it’s still a very, very good fastball, and 100 mph is 100 mph. But it’s pretty reliant on that elite velocity (and good command) to be effective, making it imperative that the Dodgers help him get back to his 2023 form.
1) Splitter
Of course, it’s always nice when your triple-digits heater isn’t the most dangerous weapon in your repertoire. For Sasaki, everything else is just window-dressing for his splitter, which just might be the single weirdest, most unique pitch on planet Earth right now.
Sasaki’s split produced a 57.1 percent whiff rate in 2024; for context, the Major League average on splitters was 34.5, and that 57.1 mark would’ve ranked second in the entire league (behind only Fernando Cruz, a former Cincinnati Reds reliever now with the New York Yankees). Nobody can figure it out, probably because it’s unlike any other splitter: Sasaki gets so little spin on his split that it behaves more like a knuckleball than anything else, darting in any given direction.
A good look at Sasaki’s release point (fastball vs. split)
With a pitch like that in his arsenal, Sasaki would be tough to deal with under any circumstances. Combine that with another viable breaking ball and a 100-mph heater that batters have to try and time up, and you can understand why the entire league was falling over themselves to land the righty this winter.
