Peralta (shoulder) threw off flat ground Saturday, Adam McCalvy of MLB.com reports.
Peralta has been on the injured list for just over a week due to shoulder fatigue, but he's now been cleared to begin a throwing program. Manager Craig Counsell said Saturday that he "absolutely" expects the right-hander to return prior to the end of the regular season, but he'll need to make several more steps in his recovery process before he's cleared to be activated.