Christian McCaffrey

49ers head coach Kyle Shanahan said Christian McCaffrey is dealing with a calf strain and Achilles tendinitis.

Shanahan said McCaffrey dealt with similar issues last January during the team’s run to the Super Bowl. If Week 1 had been a postseason game, Shanahan said, CMC would have suited up. Look for the Niners to exercise extreme caution with McCaffrey in the coming weeks, riding Jordan Mason as the lead back until McCaffrey is ready to return to action. ESPN’s Adam Schefter said Monday night that CMC has a “real chance” of sitting in Week 2 against Minnesota. NFL Network’s Ian Rapoport said McCaffrey “feels like a long shot” for Week 2.