Perdomo (back) was reinstated from the 10-day injured list and optioned to Triple-A Nashville on Thursday.
Perdomo had been on the injured list since May 30 due to a lower back strain, but he began a rehab assignment June 20. The southpaw made five appearances with the Triple-A club and allowed no hits and a walk while striking out 10 in five scoreless innings. He'll remain in the minors but could return to the Brewers as a low-leverage reliever at some point.