The team announced that Sims is expected to have a recovery timetable of 12-14 weeks.
In a best-case scenario, he won't be ready until midseason. That would make him a prime candidate for the injured reserve-designated for return tag.
Smith and offensive coordinator Jeff Tedford have envisioned a committee backfield, with Sims playing an integral role.
While the injury disrupts Smith's plans, it's music to the ears of fantasy football players worried about Martin's workload taking a major hit in 2014.