Cody Bolton exited Houston's Sunday start in Seattle during the second inning with mid-back tightness after being struck in the back by a 102.5 mph line drive in his previous appearance.

Bolton had his first major league start last week, lasting 4 1/3 innings in a 9-7 loss despite the line drive impact.

Astros manager and an athletic trainer visited the mound as Bolton left the game, and he did not return due to the back issue.

The report frames Houston's rotation instability and ongoing injury problems on the road trip, without predicting Bolton's prognosis or return date.

Manager Joe Espada acknowledged the staff’s struggles with throwing strikes and the toll injuries are taking as he reshapes the pitching staff.

The pitching injuries are affecting the Astros’ offense and overall performance, contributing to bullpen and rotation instability on the road trip.

Sources, including Adam Wexler and MLB.com’s Brian McTaggart, corroborate Bolton’s injury and the broader pitching crisis.

Espada and an athletic trainer attended to Bolton after the issue escalated in the second inning as he attempted to push through the discomfort.

Beyond Bolton, Houston wrestles with injuries and moves such as Tatsuya Imai’s arm fatigue evaluation, Cristian Javier’s right shoulder strain, Hunter Brown’s right shoulder strain, and Jeremy Peña's right knee issue.

The combined injuries to new acquisition Imai, and established pitchers Javier and Brown, create a pronounced pitching crisis for the Astros.

Bolton walked three batters in the second before a mound visit led to his removal from the game.

Houston confirmed Bolton’s injury as mid-back tightness, with a trainer’s mound visit preceding his departure.