San Francisco 49ers running back Jerick McKinnon will be placed on injured reserve and is expected to require an additional procedure on his surgically repaired knee.

McKinnon, 27, missed all of last season recovering from a torn ACL in his right knee in August 2018. He had signed as a free agent from the Minnesota Vikings and expected to be the starting running back in San Francisco.

On his road back to the field, McKinnon has encountered multiple setbacks.

He was activated from the physically unable to perform list in August only to be lost before the end of the same week due to discomfort in his knee. Last week, he was back on the practice field only briefly before another issue in the same knee.

NFL Network reported the 49ers had not yet determined Friday whether McKinnon would be eligible to return from IR or be shut down for the entire 2019 season.

At that point, he would stand to make $16 million over two seasons without taking a snap, based on the structure of his contract.

In four years with the Vikings, McKinnon ran the ball 474 times for 1,918 yards (4.0 avg) and seven touchdowns. He added 142 catches for 984 yards and five scores.