Rookie Isaac Guerendo has been elevated to the 49ers’ starting running back after San Francisco had to put both Christian McCaffrey and backup Jordan Mason on the IR on the same day.
The news of McCaffrey’s time out because of injury was not a shock, but the news of Mason’s injury appeared to catch many off guard.
Mason was placed on the injured reserve with a high ankle sprain leaving Guerendo as the top back in the 49ers depth chart.
Mason’s injury occurred during Sunday’s loss to the Bills and he will miss a minimum of four games.
Guerendo has recorded 42 carries for 246 yards in 12 games this season, while putting up two touchdowns and making five catches for 19 yards.
The injury to Mason is a tough blow for a 49ers team that was already preparing itself to miss more time without McCaffrey, who suffered a PCL injury in his right knee.
Niners head coach Kyle Shanahan told reporters on Monday that McCaffrey won’t need surgery.
“I just feel for him,” Shanahan said, per ESPN. “It was a real frustrating year for him. He worked his ass off to get back to this point and I think he was really feeling good and about to take off. He just had that real unfortunate injury last night. I know he’s as crushed as anyone but he’ll get through this. He’s a hell of a player, a hell of a person and an unbelievable 49er. And he’ll be back stronger than ever next year to help us.”
Guerendo had been selected by the 49ers in the fourth round of the draft earlier this year out of Louisville and one of his two rushing TDs came in Sunday’s loss to the Bills.
He had the 49ers lone touchdown on Sunday night when he ran on second-and-8 in the third quarter.