Padres manager Jayce Tingler confirmed Monday that Johnson (groin) will open the season on the 10-day injured list, Kevin Acee of The San Diego Union-Tribune reports.
Johnson's move to the IL was fully expected after a groin strain had prevented him from making any relief appearances during Cactus League play over the past two weeks. The right-hander does at least appear to be making progress, as he was cleared to resume mound work last week. Assuming he avoids any further setbacks with the calf during his recovery program, Johnson should be ready to return from the IL in the minimum 10 days or shortly thereafter.