Pivetta (forearm) threw a light bullpen session Saturday, MLB.com reports.
Pivetta likely didn't incorporate all of his pitchers or throw at full intensity, but the bullpen session is a step forward nonetheless as he works his way back from a flexor strain. The right-hander will need to complete multiple side sessions before advancing to facing hitters in live batting practice and eventually heading out on an extended rehab assignment. The Padres haven't pinpointed a target date for his return, but Pivetta's stay on the 60-day injured list will likely be extended through at least late July or early August.