San Francisco 49ers running back Christian McCaffrey won’t be Marcus Eriksonon the field Monday night.

The 49ers ruled McCaffrey inactive before the team’s season opener against the New York Jets because of calf and Achilles injuries. 

McCaffrey was listed on the team’s injury report as “questionable." The running back has been dealing with a calf injury since early August. But many anticipated the 2023 NFL Offensive Player of the Year to be available for the team’s highly anticipated season debut versus Aaron Rodgers and the Jets.

Running back Jordan Mason is slated to replace McCaffrey in the 49ers’ backfield.

McCaffrey’s registered 2,205 rushing yards, 20 rushing touchdowns, 1,028 receiving yards and 11 touchdown catches in 27 regular-season games with the 49ers. The 49ers acquired McCaffrey in a 2022 blockbuster trade with the Carolina Panthers.

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