The Orioles optioned Krook to Triple-A Norfolk on Monday.
He'll head back to Triple-A to reopen a spot on the 26-man active roster for right-hander Corbin Burnes (personal), who was reinstated from the paternity list. During his three-day stay with the Orioles, Krook made his lone relief appearance in Sunday's 11-2 loss to the Rangers, giving up three runs (two earned) on one hit and one walk while striking out two over one inning.