Then, he took a giant step forward in 2024, posting a 1.95 ERA (156 ERA+) with a 22% strikeout rate and 11% walk rate across 120 innings, including a career-best 13 strikeouts across seven innings of one-run ball on June 28.

While his underlying metrics suggested some degree of overperformance (99 FIP-, 101 kwERA-), he still played a key role in the team’s pennant run and firmly established himself as a pillar of the rotation. His season ended on a tough note, however, as he entered in relief in Game 6 of the Japan Series and allowed five earned runs, sealing the team’s elimination.

Unfortunately, 2025 became a lost season for Stewart, as he missed the entire year with another abdominal injury and was sidelined while his teammates returned to the Japan Series and took home the championship without him.

The Return

Determined to reestablish himself as a force to be reckoned with in the final year of his contract, Stewart impressed in spring training this year, flashing his plus stuff. He fired two shutout innings against Samurai Japan in a pre–World Baseball Classic exhibition and went on to deliver a healthy preseason, securing a spot in the Opening Day rotation.

Through his first two regular season starts, Stewart has picked up wins in both outings while posting a 23% strikeout rate and 6% walk rate, ranking in the 97th percentile in NPB in called strike plus whiff rate.

“I’m just happy to be back here,” Stewart said after his first start. “I didn’t throw last year, but I’m home,” he added in Japanese.

Stewart gets a big strikeout against Misho Nishikawa on April 6.

The SoftBank starter is sitting 94 mph on his fastball (touching 97) and locating it effectively at the top of the zone to set up his high-70s curveball, which is averaging over 3,100 RPM and has been his calling card since high school.

What stands out most, however, is his increased comfort with a mid-80s splitter as a true putaway weapon. He’s boosted the usage on it from 22% versus righties and 25% versus lefties in 2024 to 35% against both, generating a 59% whiff rate overall.