Baltimore optioned Nunez to Triple-A Norfolk on Tuesday.
Nunez was last in action on Sunday, when he pitched one scoreless inning against San Diego. On the campaign, the right-hander has posted a 4.98 ERA, 1.28 WHIP and 38:14 K:BB through 34.1 innings. The 24-year-old will head down to Norfolk to make room for Ryan Helsley on the active roster.