Morejon was placed on the minor-league disabled list with a small triceps issue, Jeff Sanders of The San Diego Union-Tribune reports.
Fortunately, Morejon isn't dealing with any issue to his ulnar collateral ligament. The plan is to shut the prospect down for 10 days before allowing him to build back up with a restricted pitch count. It's Morejon's second trip to the disabled list stint in the past two months -- his other due to a hip flexor issue -- so the Padres figure to proceed cautiously with the young southpaw.