Carpenter was placed on Triple-A Toledo's 7-day injured list Aug. 2 due to a left elbow impingement.
Toledo shut Carpenter down one day after he surrendered six runs in five innings in his start against Indianapolis. Had he not succumbed to an injury of his own, Carpenter likely would have been an option to make a start for the big club Friday against the Royals. The Tigers, who are running a six-man rotation this week due to a doubleheader Tuesday versus the White Sox, have yet to decide on a spot starter.