Tatsuya Imai — 2026 Season

2026 Season Highlights

As of 7/15, Tatsuya Imai remains a fixture in the Astros' starting rotation. He has racked up strikeouts but has also allowed his share of runs, making for an up-and-down season so far. After establishing himself as the ace of the Saitama Seibu Lions in Japan, he moved to MLB in 2026 and has held a rotation spot since Opening Day. Tightening up his command looks like the key to smoothing out his results going forward.

Tatsuya Imai (Houston Astros) was drafted first overall by the Seibu Lions in 2018 out of Sakushin Gakuin High School in Tochigi Prefecture. He overcame early shoulder injuries and emerged as a dominant ace from 2022 onward — winning the NPB strikeout title in 2024 and posting a career-best 1.92 ERA in 2025 before making the leap to MLB. 【Pitch Arsenal & Style】Imai works primarily off a mid-90s (150km/h+) four-seam fastball that touches 97 mph, paired with a sharp diving forkball (splitter family, ~85 mph with negative-vertical break) and a sweeping slider in the low-to-mid 80s. The fastball-forkball combination is built on tunneling: both pitches share a release point and arm speed before the forkball drops late, which is why opposing hitters chase below the zone at high rates. The forkball generates elite swing-and-miss rates — evidenced by 13 strikeouts in his first three MLB starts (K/9: ~13.5, swinging-strike rate above 14%). Walk prevention (11 BB in 8.2 IP, BB/9 ~11.4) remains the key area for improvement on his way to becoming a front-of-rotation arm. The Astros' development plan focuses on improving Zone% (in-zone pitch rate) without sacrificing the chase-inducing forkball usage. 【Team & Environment】The two-time World Series champion Astros (2017, 2022) are renowned for elite pitching development — turning Justin Verlander, Cristian Javier, Framber Valdez, and Luis García into front-line arms. Pitching coach Josh Miller and general manager Dana Brown have publicly emphasized command refinement as the next step for Imai. Minute Maid Park is pitcher-friendly with one of the AL's lower home run park factors. The retractable roof neutralizes weather variance — a comfort for a pitcher transitioning from NPB stadium conditions. Imai joins a rotation that has consistently ranked top-5 in starter ERA over the past five seasons, giving him strong pitch-mix and game-plan templates to absorb. His 2026 MLB stats — ERA, K, BB, K/9, BB/9, FIP, WHIP — are updated daily on this page after every start.

• 1He has picked up wins along the way, but starts marred by run-scoring innings have been common too, leaving his results inconsistent so far.
• 2In Japan, Imai was the ace of the Saitama Seibu Lions, leading his league in strikeouts in 2024 and posting his career-best season for consistency in 2025. He signed a multi-year deal to join the Astros and has held a rotation spot since Opening Day 2026.
• 3His trademark strikeout stuff remains sharp, and he flashed an especially high strikeout rate earlier in the season. Tightening up his command looks like the next step toward more consistent starts.