The Twins made the move Wednesday, and right-handed reliever Alan Busenitz was recalled from Triple-A Rochester to take Santiago's place on the roster. Busenitz was just sent down Saturday.
Santiago, who spent time on the disabled list last month with a left shoulder strain, is 4-8 with a 5.63 ERA in 70 1/3 innings, with 31 walks and 51 strikeouts. He is 0-6 in his last seven starts, with four lasting fewer than four innings. Santiago was pulled early from his outing Sunday in part because manager Paul Molitor was concerned about his strategy of decreasing velocity for sharper command.