Padres manager Craig Stammen told reporters Wednesday that Pivetta was diagnosed with a right flexor strain, Jeff Sanders of The San Diego Union-Tribune reports.
Per Annie Heilbrunn of the San Diego Sports Association, Stammen believes that Pivetta is looking at "weeks, maybe months" of rehab and rest. That kind of timeline indicates that Pivetta will be out of action until the summer, potentially through the All-Star break in mid-July. Matt Waldron (lower body) is slated to take Pivetta's spot in the rotation later this week once the former is activated from the 15-day IL.