The Marlins announced Castano will be called up from Triple-A Jacksonville to start Thursday's game in Cincinnati, Jordan McPherson of the Miami Herald reports.
Castano will be entering the rotation as a replacement for Max Meyer (elbow), who was moved to the 15-day injured list over the weekend. Before he was optioned to Jacksonville on July 15, Castano made nine appearances (six starts) for Miami, posting a 3.86 ERA, 1.40 WHIP and 20:9 K:BB across 35 innings. The southpaw may just be making one turn through the rotation before heading back to Triple-A, as Jesus Luzardo (forearm) could be ready to come off the 60-day IL when the Marlins next require a fifth starter Aug. 2.