Contreras (shoulder) is expected to return to the Triple-A Indianapolis rotation this week, Jason Mackey of the Pittsburgh Post-Gazette reports.
Contreras was scratched from his last scheduled start Friday versus the Triple-A affiliate of the Blue Jays due to stiffness in his right shoulder, but it's apparently not a serious concern. The 23-year-old is working on a new sinker and has fared well overall since the Pirates optioned him to the minors before the All-Star break.