Marinan (oblique) has allowed seven runs (six earned) on eight hits and three walks while striking out two across six innings in five appearances for High-A Dayton since being reinstated from the 7-day injured list Aug. 6.
High-A Dayton placed Marinan on its 7-day injured list Tuesday with a right oblique strain.
Marinan cleared waivers Thursday and was outrighted to High-A Dayton, C. Trent Rosecrans of The Athletic reports.
Marinan was designated for assignment Saturday.
The Reds optioned Marinan to Double-A Chattanooga on Thursday, Charlie Goldsmith of The Cincinnati Enquirer reports.
Marinan had his contract selected by the Reds on Friday.
Marinin and minor-league pitcher Aneurys Zabala were traded Wednesday from the Dodgers to the Reds in exchange for reliever Dylan Floro, minor-league pitcher Zach Neal and international signing bonus pool space.