Castano was recalled from the Marlins' alternate training site Thursday, Jordan McPherson of the Miami Herald reports.
The Marlins will add a fresh arm in Castano to the bullpen after sending down Jordan Yamamoto in a corresponding move. Castano has a 4.11 ERA, 1.57 WHIP and 8:8 K:BB in 15.1 innings. He could start a game in the coming days, as the Marlins are set to play 15 games in the next 11 days.