President of baseball operations John Mozeliak revealed Wednesday that Mikolas is dealing with shoulder stiffness, but the issue isn't believed to be a long-term concern, Zachary Silver of MLB.com reports.

EDGE Analysis

Mikolas was scratched from a scheduled simulated game appearance Monday, but until this point, the change had been dismissed as unrelated to any health concern. Mozeliak's comments Wednesday naturally cast a different light, although the team executive added the prognosis from team trainers was positive and the hope was the stiffness was "not something that lingers for a week or two." For the time being, Mikolas still appears set for a side session at some point this coming weekend, although those plans are naturally subject to change.