49ers' Christian McCaffrey placed on IR with calf, Achilles injuries

The San Francisco 49ers are going to be without star running back Christian McCaffrey for the next four games, at least, before the team assesses whether he can return in mid-October.

The news comes Saturday after it was previously reported that McCaffrey was ruled out of the Niners' 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, according to 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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