San Francisco 49ers star running back Christian McCaffrey will miss the entire preseason and a few weeks of practice due to a calf strain sustained during training camp. Head coach Kyle Shanahan confirmed that while the injury is not severe, McCaffrey will be sidelined to ensure his readiness for the season opener against the New York Jets on September 9. The 49ers have signed veteran Matt Breida to bolster the backfield, as backup running back Elijah Mitchell is also nursing a hamstring injury. McCaffrey, who had a stellar 2023 season with 1,459 rushing yards and 21 touchdowns, is a crucial player for the team. Despite these setbacks, the team remains optimistic about McCaffrey's return for the regular season.