The Padres optioned Nunez to Triple-A El Paso on Friday.
After giving up two earned runs over 4.2 innings during his first nine days as a major leaguer, Nunez will head back to Triple-A to clear room for Ryan Bergert's (forearm) return from the IL. The 26-year-old Nunez also owns a 2.40 ERA and 1.07 WHIP over 30 innings between Double-A and Triple-A this season, and if he continues at that rate, he should be able to make another appearance for the Padres at some point down the line.