Kyle Shanahan: 49ers have to be careful with Christian McCaffrey’s Achilles tendinitis

49ers head coach Kyle Shanahan said running back Christian McCaffrey is dealing with both a calf injury and Achilles tendinitis, and he says the team will be cautious about not allowing McCaffrey to aggravate the injury.Shanahan said on a conference call with reporters that the injury McCaffrey is dealing with now is similar to the calf injury that had him listed on the injury report before the playoff game against the Packers in January. McCaffrey played through that injury, and Shanahan said he would be playing now if it were the playoffs, but in the regular season they're exercising more caution."I believe they're similar, I know it was a calf then and it's a calf now," Shanahan told reporters on a conference call. "You guys can ask Christian more on that. Definitely, I believe if it was a playoff game he would've played. It's not just the calf, it's the Achilles, and the Achilles is tendinitis, and that stuff comes and goes. And when it is acting up it's something you've got to be very careful about. Christian is very diligent about that stuff. If it was a playoff game, he made it very clear to me he believed he could go. But when you hear that type of stuff, and it's not a...