SANTA CLARA, Calif. (AP) — San Francisco 49ers running back Jeff Wilson Jr. will miss the start of the 2021 season after undergoing surgery on his injured knee.

General manager John Lynch said Wednesday that Wilson injured his knee last week following practice and a weightlifting session.

Lynch said Wilson felt a “pop” in his knee when he stood up Thursday after practice and an MRI determined he tore his meniscus. Wilson underwent surgery Friday and is expected to miss four to six months.

Lynch called the injury a “speed bump” and said Wilson's mindset has "already shifted to recovery.”

Wilson will begin the season on the physically unable to perform list, which will force him to miss at least the first six weeks of the season, Lynch said.

Wilson signed a fully guaranteed $2.05 million contract for 2021 this offseason. Because the injury happened when he was at the team facility, Wilson will be paid no matter when he's able to return to the field.

Wilson led the Niners in rushing last season with 600 yards and seven touchdowns on 126 carries as mainly a backup to Raheem Mostert. Wilson also had 13 catches for 133 yards and three TDs, with his 10 total touchdowns tied for the most by a San Francisco player since Vernon Davis had 13 in 2013.

The Niners still have good depth at running back behind Mostert after drafting Trey Sermon in the third round and Elijah Mitchell in the sixth round.

San Francisco also signed Wayne Gallman this offseason after he rushed for 682 yards last season for the Giants and bring back Jamycal Hasty, who ran for 148 yards in limited action for the Niners last season.

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