McCaffrey, Shanahan explain 49ers’ lack of RB rotation

SANTA CLARA — Christian McCaffrey rarely has been taken off the field since returning from an eight-game absence due to bilateral Achilles tendinitis, which the 49ers running back shared is not his decision. "I think that's a narrative that kind of goes on," McCaffrey said Wednesday. "If I feel like I can't be my best out there, I'll come off the field. I don't handle my own snaps is the short answer. If I'm out there, I'm full speed and I'm ready to go." Since the reigning NFL Offensive Player of the Year's return in Week 9, his backup Jordan Mason has registered six carries for 26 yards, and rookie Isaac Guerendo has run only once for no gain. In Weeks 1 through 8, Mason was dominating the line of scrimmage with 134 carries for 685 yards for a 5.1-yard average. Kyle Shanahan, who is known for going with the hot hand, provided a little more explanation as to why both Mason and Guerendo have not been on the field much since McCaffrey's return. "Even when Mason was going a ton, we didn't get Isaac a lot," the 49ers coach said Wednesday. "We're not just a big three-man-rotation team, especially when you have a solidified starter. We're not trying to get Christian off the field...