The Diamondbacks optioned Misiewicz to Triple-A Reno on Sunday.
Misiewicz was sent down to make room on the 26-man roster for outfielder Dominic Fletcher, who was called up from Triple-A in a corresponding move. In four appearances out of the Arizona bullpen, Misiewicz has logged a 3.86 ERA and 1.50 WHIP over 4.2 innings.