Armstrong (calf) didn't record a strikeout while allowing one run on two hits in one inning during a rehab appearance Friday with Triple-A Columbus.
Armstrong was initially placed on the shelf July 25 due to a left calf strain before being transferred to the 60-day IL less than two weeks later. He's eligible for reinstatement Sept. 23 and should be on track to rejoin the Guardians on that date or shortly thereafter, assuming his subsequent rehab appearances go well.