Stowers exited Thursday's contest against the Royals with left hamstring tightness, Christina De Nicola of MLB.com reports.
Stowers was hit by a pitch in the foot during top of the seventh frame, but it was ultimately hamstring discomfort that resulted in him being removed in the eighth inning. The 28-year-old will likely undergo additional imaging and should have his status updated in the near future. It's worth noting that a strain of the same hamstring put Stowers on the injured list for a couple weeks in August.