The San Francisco 49ers are grappling with a critical situation at the running back position following an injury to rookie Isaac Guerendo. Coach Kyle Shanahan confirmed that Guerendo is dealing with a foot sprain, which leaves his status uncertain for the upcoming Thursday night game against the Rams. This follows a notable performance where Guerendo saw a promising start but left the game due to injury, shaking up an already precarious depth chart impacted by injuries to Christian McCaffrey and Jordan Mason. The team remains hopeful that Guerendo may still be available, but the decision will likely come down to a game-time evaluation.