McCaffrey (calf), who was placed on injured reserve Saturday, is "likely to be out six weeks or potentially more" while he recovers from Achilles tendinitis, Ian Rapoport of NFL Network reports.
McCaffrey's placement on IR ensures that he'll miss the 49ers' next four games, but Rapoport suggests that the team is preparing for the star tailback to miss additional time beyond that. The 28-year-old isn't helped by the fact that the 49ers will play a Thursday night game in Seattle in Week 6, the first game in which McCaffrey would be eligible to return from IR. While Rapoport notes that McCaffrey won't be at an elevated risk of tearing his Achilles once he eventually plays again, the running back's Achilles tendinitis is regarded as a painful injury that will require rest and rehab for him to properly heal. Jordan Mason played 81 percent of the 49ers' offensive snaps and took on 29 touches in a Week 1 win over the Jets, and he looks like he could be in line for a heavy workload for the duration of McCaffrey's absence.