Kranick was diagnosed with a Grade 2 left hamstring strain Thursday, Anthony DiComo of MLB.com reports.
Manager Carlos Mendoza said Kranick will be shut down for "a while" and will begin the regular season on the injured list. A clearer picture regarding Kranick's return timeline should emerge once he resumes throwing, but the 26-year-old right-hander is officially out of the race for an Opening Day rotation spot.