The Houston Astros have reached an agreement with Japanese right-hander Tatsuya Imai, locking up one of the most sought-after pitchers to come out of Nippon Professional Baseball this offseason.
According to multiple reports on Thursday, the deal was finalized just ahead of the expiration of Imai’s 45-day posting window, which was set to close Friday evening. The contract spans three years and could be worth as much as $63 million, with opt-out clauses after each season. The agreement includes $54 million guaranteed and an average base salary of $18 million per year, plus performance incentives that could push annual earnings to $21 million, according to MLB reporter Jon Heyman.
At that figure, the contract gives Imai one of the highest average annual values ever for a Japanese-born pitcher, trailing only Yoshinobu Yamamoto. Houston will also owe a posting fee to Imai’s longtime club, the Seibu Lions, calculated based on the final value of the deal. That fee does not count toward Major League Baseball’s competitive balance tax.
Imai, who turns 28 in May, spent his entire professional career with Seibu and emerged as one of NPB’s premier starters over the past several seasons. In 2025, he delivered a dominant campaign, going 10-5 with a 1.92 ERA, 178 strikeouts and 45 walks across 163⅔ innings. He struck out roughly 28% of opposing hitters, far above the league average, while showcasing mid-to-upper-90s velocity and a sharp breaking pitch delivered from a low release point.
Across eight seasons in Japan, Imai compiled a 58-45 record with a 3.15 ERA and 907 strikeouts in just under 964 innings. While command was an early-career issue, his recent improvements convinced teams he could slot quickly into the middle of a major league rotation, with upside beyond that.
Houston reportedly passed on longer offers with lower yearly pay in favor of a shorter contract that gives Imai flexibility while providing the Astros an immediate boost near the top of their rotation. Pending a completed physical and finalized paperwork, the signing positions Imai to make an instant impact in 2026 as Houston reinforces its pitching staff.
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