Santillan was placed on the 7-day DL on Thursday at Low-A Dayton with shoulder stiffness.

EDGE Analysis

The big righty's stuff has always been filthy, with the potential for two plus-plus pitches in his fastball and curveball, and he had finally started to make major improvements to his control this season before the injury. After posting a 17.4 percent walk rate in 30.1 innings at Low-A last year, he had managed a 9.5 percent walk rate in 58.2 innings this season. He is still walking too many hitters, but at least he is now in a range as a 20-year-old that allows evaluators to give him a chance of ending up in the rotation long term. Hopefully this injury is just stiffness, and he can return to the mound and pick up where he left off in the coming weeks.