Morejon was scratched from his last scheduled outing due to neck stiffness, Dennis Lin of The Athletic San Diego reports.
The 19-year-old left-hander isn't expected to miss an extended amount of time with the issue, so he'll be considered day-to-day moving forward. Morejon has made seven starts for High-A Lake Elsinore this season, posting a 3.67 ERA and 1.32 WHIP with 36 strikeouts and 14 walks over 34.1 innings.