The Reds informed Peralta on Tuesday that he would be included on the Opening Day roster, Bobby Nightengale of The Cincinnati Enquirer reports.
Peralta and Robert Stephenson claimed the final two available spots in the bullpen after the Reds reassigned Matt Wisler to the minors. The 27-year-old lefty has made 138 appearances in relief for Cincinnati over the past three seasons, submitting a 4.68 ERA, 1.57 WHIP and 7.1 K/9.