Carlton was optioned to Triple-A Toledo following Tuesday's win over the White Sox, Evan Woodbery of MLive.com reports.
Carlton has made four major-league appearances since the start of September, and he recorded a 4.91 ERA and 2.73 WHIP in 3.2 innings. However, he'll lose his spot in the Tigers' bullpen since Joe Jimenez (illness) will be reinstated from the COVID-19 injured list Wednesday.