Tatsuya Imai's return to the mound was supposed to be a fresh start, but Tuesday night against the Mariners turned into another tough chapter for the Astros right-hander. Making his first appearance since April 10 after dealing with arm fatigue, Imai struggled through four innings, surrendering six runs in a 10-2 loss at Daikin Park. Control issues continued to plague him, as he issued three walks and hit two batters, bringing his season totals to 14 walks and three hit batters over just 12⅔ innings in 2026.

Despite the rough outing, Astros manager Joe Espada made it clear that Imai will get another chance. "He's going to make his next start," Espada told reporters after the game. "We wanted him to pound the zone with two pitches that he can command and control. There were opportunities against some of those lefties, some windows, he could have used split-finger and changeup."

Imai stuck to a two-pitch game plan Tuesday, relying exclusively on fastballs and sliders—with no splitters at all. Interestingly, he swapped his four-seam fastball for a sinker, a pitch he hadn't thrown all season, even during minor-league rehab starts. The sinker was effective, but the slider proved costly: four of the five hits Imai allowed, including both home runs, came off that pitch. It was a step forward in some areas, but still a disappointing overall performance.

Four starts into his MLB career, Imai's numbers are tough to ignore: a 9.24 ERA with underlying metrics like a 6.67 FIP and 6.62 xERA. On one hand, it's only four starts and 12⅔ innings, with the added challenge of adjusting to a new country and a brief injury layoff. On the other hand, those four starts have been as difficult as they come. "There's a lot more thinking on the mound compared to Japan because there's a lot more change in the States and I have to adjust more," Imai said through an interpreter. "I have to think more aggressive throwing in the zone and trying to get an out."

Imai's struggles are part of a larger problem for the Astros rotation. Houston has used 12 different starters this season, the most in baseball, and their starters rank last in ERA (5.23) and 24th in WAR (1.8). The bright spot has been Spencer Arrighetti and Peter Lambert, who have combined for a stellar 2.32 ERA in 10 starts. The rest of the rotation? A 6.47 ERA in 33 starts—a stark contrast that highlights the team's ongoing pitching woes.

Tuesday's loss dropped the Astros to 16-27 on the season, and their postseason odds have taken a hit, falling from 32.8% to just 8.2% since Opening Day, according to FanGraphs. The Mariners, meanwhile, won for the fourth time in six games and sit at 21-22. For Imai and the Astros, the road ahead is steep, but with Espada's vote of confidence, the Japanese right-hander will have another chance to turn things around. Whether he can find his footing in the big leagues remains one of the most compelling storylines of Houston's season.