The San Francisco 49ers will be without star running back Christian McCaffrey again in Week 2.

The 49ers ruled McCaffrey out for Sunday as the team travels to Minnesota to take on the Vikings. McCaffrey has been dealing with calf and Achilles injuries and the running back was sidelined in San Francisco’s Week 1 win against the New York Jets.

On Friday, 49ers head coach Kyle Shanahan didn’t rule out the possibility of the team placing McCaffrey on injured reserve, which would keep him out a minimum of four games.

“It’s something we're considering now," Shanahan told reporters. "Yesterday was his worst day. It's on and off, but with yesterday, having the most pain, it’s something we're going to be discussing here in the next 24 hours"

The 49ers will rely on running back Jordan Mason with McCaffrey missing his second straight game. Mason had career-highs in both carries (28) and rushing yards (147) in Week 1.

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"I think (Mason) did a good job coming in," 49ers quarterback Brock Purdy said after last week’s win. "Obviously, Christian is the best in the league at running back and what he does. I’m not taking anything away from that. But I think (Mason) did a good job of coming in and filling in his void and doing his job allowing other guys to get open and allow us to run our offense."

McCaffrey won NFL Offensive Player of the Year in 2023 and helped the 49ers reach Super Bowl 58. He’s produced 2,205 rushing yards, 20 rushing touchdowns, 119 catches, 1,028 receiving yards and 11 touchdown receptions in 27 regular-season games in San Francisco.

The 49ers acquired McCaffrey in a blockbuster trade with the Carolina Panthers in October 2022.

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