The Saitama Seibu Lions are set to post right-handed pitcher Tatsuya Imai for MLB teams ahead of the 2026 season. Imai has proven to be a very appealing option for MLB teams seeking middle-of-the-rotation arms with a much higher upside.
Japanese Pitcher Tatsuya Imai Set to Be Posted
NPB Career
Imai’s statistical progression in recent seasons has caught the attention of MLB scouts from every team. In 2024, he recorded 10 wins, 8 losses, and a 2.34 ERA over 173 innings, establishing himself as an NPB ace. His 2025 campaign has been even more impressive, featuring a 1.77 ERA in 157 innings.
One guy who I think could be an under the radar option for the Red Sox rotation this offseason is Tatsuya Imai out of Japan, who’s expected to be posted.
2025 in NPB: 24 GS, 1.92 ERA, 9.8 K/9, 2.5 BB/9
60 FB, 55 SL, 50 CH; Used Splitter & CB more this year. pic.twitter.com/3IVd0gS2S3
— Robbie Hyde (@gingersnaphyde) October 18, 2025
Imai’s success comes from a diverse pitch mix, something all MLB teams long for. His fastball is his main pitch, complemented by a sharp slider, nasty cutter, and deadly splitter. Early in his career, control issues limited his ceiling, but he has since refined his command and pitch tunneling to become far more efficient. Imai has always been good at sequencing his arsenal as he has evolved as a pitcher, making him less predictable. With the advance scouting in MLB, Imai might not have reached his ceiling yet.
Imai’s MLB Potential
Unlike some power arms from Japan, Imai relies more on command and feel than on pure velocity. Scouts value his repeatable delivery, rhythm, and mental toughness on the mound. With the transition from NPB to MLB being tough, mental toughness becomes even more essential. Imai is a very appealing candidate for MLB teams seeking mid-rotation reliability rather than a volatile flamethrower.
While he may not yet have the global name recognition of Rōki Sasaki or Yoshinobu Yamamoto, Tatsuya Imai’s command, durability, and quiet dominance have made him one of the most respected pitchers in Japan and one of the most appealing to MLB teams. As the posting period approaches, his name will be one to watch closely. Imai is a potential under-the-radar addition who could make a major impact on an MLB rotation by 2026.
Main Photo Credit: Bob Kupbens-Imagn Images
