In 2025, Roki Sasaki had one of the more unusual rookie seasons in recent Los Angeles Dodgers memory.

After being the most in-demand international free agent since his future teammate, Shohei Ohtani, with Blue Jays fans in particular taking his near-signing incredibly hard, Sasaki struggled early on as a starting pitcher for the Dodgers, landing on long-term IL with a right shoulder impingement. From there, Sasaki’s season looked finished, but in an unlikely twist, the rookie pitcher tried his hand out of the bullpen in OKC to impressive results, becoming the team’s de facto closer during the playoffs despite spending his entire career in Japan as a starter.

With a World Series win on his resume and a World Series ring coming soon, what can Sasaki do to build on his debut campaign in 2026? Well, according to Fabian Ardaya of The Athletic, the answer is clear: Sasaki needs to up his velocity to become a consistent fastball thrower in the starting lineup.

“The biggest thing, along with health, the Dodgers can hope to bank on from Roki Sasaki’s midseason transformation is his mechanics. The cues they implemented to get him to use his lower half more were what was needed to get his velocity back to a place where his fastball couldn’t get crushed in the strike zone. That allowed Sasaki to be in the strike zone more often, which helped out his unique splitter,” Ardaya wrote.

“If the velocity is close to where it needs to be, then Sasaki at least has the building blocks for an effective starter, even if his new cutter doesn’t wind up being a viable pitch.”

While Sasaki turned in some of the most effective games of his short MLB career during the postseason, he did so largely with his splitter, with opposing teams able to get on a fastball that rarely cracked the high 90s, let alone over 100. If Sasaki is going to be able to take down the same batters multiple times in the same game, he’s going to need to place his typically effective fastball in the strike zone to set up his splitter, instead of the other way around.