Houston Astros right-hander Tatsuya Imai will pitch out of the bullpen during the team’s series against the Rangers, according to manager Joe Espada. The decision follows Imai’s short outing Monday against the Angels in Anaheim, where he recorded only two outs and saw his season ERA climb to 5.83 over 58 2/3 innings across 15 starts.
Astros Move Struggling Tatsuya Imai to Bullpen Role
The transition comes after a rocky start to the right-hander’s Major League career. Signed to a three-year, $54 million contract in the offseason following a stellar career in Japan, Imai struggled to find consistency in the rotation. According to Espada, the team met with Imai in Anaheim to identify mechanical adjustments.
Did you know? Tatsuya Imai was a three-time All-Star in Nippon Professional Baseball (NPB), posting an ERA under 3.00 and striking out more than a batter per inning in each of his final three seasons with a career-best 1.92 ERA in 2025.
Imai previously cited various adjustments to the Major Leagues, including the condition of pitching mounds, different-sized baseballs, and altered eating schedules. Despite throwing a slider 45.4 percent of the time and a four-seamer 42.7 percent, Imai has struggled with control, issuing 40 walks in 58 2/3 innings for a rate of 6.14 walks per nine innings, though he maintains a 31.6 percent whiff rate and a 27.2 strikeout rate.
“Hopefully we can give Imai a few innings during this series, but for now we have a pretty good plan here moving forward to see if we can get him back [on track],” Espada said. “We’re going to go one inning at a time and make sure we give him enough time to bring him into the game.”
Rotation Adjustments and Potential Replacements
With Imai moving to relief, right-hander Cristian Javier is positioned to return to the starting rotation for Sunday’s series finale against the Rangers. According to team observations, Javier threw five scoreless innings in relief Monday and completed a bullpen session Friday at Daikin Park, which typically precedes a start by two days. However, Espada stopped short of formally committing to Javier as Sunday’s starter, noting that right-hander Peter Lambert also threw a bullpen session Friday and remains an option to start on four days of rest.
The Astros have gradually reinforced their pitching staff, welcoming back veterans Hayden Wesneski and Ronel Blanco from Tommy John surgery in recent weeks. Lambert leads the team with 18 starts this year, followed by Spencer Arrighetti with 17 starts and Mike Burrows, who is currently on the injured list after making 17 starts. Ace Hunter Brown also made his 10th start of the season against the Rangers.
“Eventually I want to be back as a starter,” Imai said regarding his new role. “The Astros signed me as a starter, so that’s how I want to perform. But as of right now, that’s what the team decided, so I just want to perform well and get the win as a team.”
Frequently Asked Questions
Why did the Astros move Tatsuya Imai to the bullpen?
According to manager Joe Espada, the move is designed to help Imai get back on track after struggling to a 5.83 ERA in his first 15 Major League starts, which included three outings where he failed to escape the first inning.
What are Tatsuya Imai’s primary pitches?
Imai relies heavily on a slider, which he throws 45.4 percent of the time, and a four-seam fastball, thrown 42.7 percent of the time, backed by an elite 31.6 percent whiff rate.
Who might replace Imai in the starting rotation?
Right-hander Cristian Javier and right-hander Peter Lambert are both candidates to start Sunday’s series finale against the Rangers after throwing bullpen sessions on Friday.
What was Tatsuya Imai’s record before joining MLB?
Imai was a three-time NPB All-Star who went 10-5 with a 1.92 ERA and 178 strikeouts over 163 2/3 innings during the 2025 season in Japan.
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