Krook was acquired by the Orioles from the Yankees on Sunday in exchange for cash considerations.
The left-hander was designated for assignment by New York on Tuesday, and Baltimore opted to trade for him rather than risk another team claiming him through waivers. Krook allowed 11 earned runs in four big-league appearances last season but had a 1.06 ERA, 1.06 WHIP and 55:26 K:BB across 34 innings at Triple-A.