49ers' McCaffrey and Mason to IR, McCaffrey's season in jeopardy

San Francisco 49ers running backs Christian McCaffrey and Jordan Mason will be placed on injured reserve following injuries sustained in a recent game. McCaffrey, who has a PCL injury in his right knee, will miss the rest of the regular season, while Mason suffered a high-ankle sprain. Rookie Isaac Guerendo is expected to step up as the team's top back. Additionally, defensive tackle Kevin Givens will also be placed on IR, and the team is monitoring other injured players as they prepare for their next game against Chicago.