Shota Imanaga looked as polished as ever in his first Triple-A rehab start since straining his left hamstring on May 4.

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The Japanese ace took the mound for the Iowa Cubs on Friday evening in Nashville, where he struck out eight batters over 4.1 scoreless innings. He threw 72 pitches — 50 for strikes — with his fastball velocity topping out at 91.2 miles per hour. He was also able to generate 10 whiffs from Nashville Sounds hitters as he dominated the Milwaukee Brewers’ Triple-A affiliate.

Imanaga landed on the 15-day IL on May 5 and has since been slowly building back up to game speed.

The Cubs assigned him to the Arizona Complex League on June 9, where he made two ACL starts. In his first start on June 9, Imanaga pitched two scoreless innings with four strikeouts. On June 14, Imanaga threw 44 pitches over four innings, striking out four once again.

Imanaga’s dazzling performance on Friday bodes well for the Cubs’ rotation, which faced another injury scare on Friday afternoon when Matthew Boyd exited his start prematurely after falling on his shoulder. While Boyd said the fall wouldn’t be an issue, the Cubs could still use the stability that Imanaga has provided — the team has won five of the eight games he’s started in 2025.

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Manager Craig Counsell said Wednesday that the team would evaluate Imanaga’s progress after the rehab start.

Marquee Sports Network’s player development analyst Lance Brozdowski told 670 The Score on Friday morning that he anticipates Imanaga rejoining the Cubs’ rotation when the team travels to play the St. Louis Cardinals next week.

“He would line up to probably pitch one of those games in St. Louis, which would be a really nice return,” Brozdowski said.

Imanaga was an anchor in the Cubs’ rotation before his injury, pitching to a 2.82 ERA this season while striking out 34 over 44.2 innings.