Isaac Guerendo says he’s ready to be the 49ers’ starting running back

The 49ers lost both first-string running back Christian McCaffrey and second-string running back Jordan Mason to injuries last week in Buffalo, leaving only rookie Isaac Guerendo available. On Sunday Guerendo will get his first career start against the Bears, and he says he's ready.Guerendo wasn't exactly happy to hear that McCaffrey and Mason are heading to injured reserve, but he is eager to prove he's up to the challenge."You don't like to hear it and it's unfortunate the way stuff happens, but that's the way this game is," Guerendo said, via 49ers.com. "Stuff happen, stuff changes quickly. I give credit to [running backs coach Bobby] Turner for preparing everyone like they are going to start the games. When a moment like this does come, you're ready for it."Guerendo, who wasn't even a starter in college until the end of his final college season, knows he's lacking in experience. But he says he is getting more comfortable with more practice time."That's one of those things that just comes with reps. The more reps you get, the more you get the feel for it," Guerendo said. "The more I've gotten, I think I've caught onto that. That's something that has helped me and will continue...