49ers' Christian McCaffrey ruled out for Sunday vs. Vikings; IR under consideration

The San Francisco 49ers are going to be without their star running back for another week.

Christian McCaffrey has been ruled out for the 49ers' Week 2 game against the Minnesota Vikings. McCaffery has been dealing with lingering calf and Achilles issues, which forced him to miss the team's 32-19 Week 1 victory over the New York Jets. 

Head coach Kyle Shanahan added that McCaffrey had his worst day Thursday in terms of pain, and the 49ers are now considering putting their standout back on IR, according to the following report from ESPN.

Jordan Mason is expected to get the start in McCaffery's absence. The third-year back out of Georgia Tech had the best game of his young career last weekend, rushing for a career-high 147 yards and a touchdown in the win. His 28 carries were the most for any 49ers player in a regular season game in 13 years.

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