49ers' Elijah Mitchell out 6-8 weeks with MCL sprain

San Francisco 49ers running back Elijah Mitchell will miss six-to-eight weeks with an MCL sprain, head coach Kyle Shanahan announced Monday, according to Matt Maiocco of NBC Sports.

Mitchell suffered the injury in the 49ers' win against the New Orleans Saints on Sunday. He left the game in the third quarter and didn't return.

"He's pretty disappointed," Shanahan said, according to David Lombardi of The Athletic.

Shanahan added, "He's had really bad luck. ... Hopefully, we can do our job here so when he comes back, we're still playing."

Mitchell suffered an MCL sprain in Week 1 against the Chicago Bears. He missed the next seven games. Sunday's contest was just his fourth of the season.

Running back Christian McCaffrey is also dealing with knee irritation, Shanahan said. McCaffrey, who the 49ers traded for on Oct. 20, is listed as day-to-day.

Jordan Mason and Tyrion Davis-Price are the other running backs on the roster.