49ers RB Jerick McKinnon to sit rest of preseason

San Francisco 49ers running back Jerick McKinnon (28) will not play for the rest of the preseason.Photo Credit: Kelley L Cox-USA TODAY Sports

49ers running back Jerick McKinnion out with knee injury

San Francisco 49ers running back Jerick McKinnon will sit out the remainder of the preseason.

McKinnon has been sidelined since injuring his right knee in practice on Aug. 12. San Francisco general manager John Lynch told KNBR 680 that McKinnon will not play until the regular-season opener.

The 49ers are also without their top running back, Matt Breida, who suffered a shoulder injury in San Francisco's preseason opener against the Dallas Cowboys.

Veteran running back Alfred Morris, who was signed by the team to a one-year contract on Tuesday, likely will see plenty of action starting with Saturday's preseason game at the Houston Texans.

McKinnon, 26, who suffered a muscle strain in his right knee, is expected to anchor San Francisco's ground game with the departure of Carlos Hyde via free agency.

Signed to a four-year, $30-million contract in March, McKinnon rushed for 530 yards and three touchdowns last season with the Minnesota Vikings. McKinnon also had 51 receptions for 421 yards and a pair of scores.

In four seasons with Minnesota, serving primarily as a backup and change-of-pace back, McKinnon recorded 1,918 yards rushing with seven touchdowns while adding 142 receptions for 984 yards and five scores in 58 games.

On Friday, the 49ers announced they have re-signed defensive back Dexter McCoil to a one-year deal and in a corresponding move placed safety Terrell Williams Jr. on the Injured Reserve List.

The 6-4, 220-pound McCoil was claimed on waivers by the 49ers from the Los Angeles Chargers last October and played in eight games, making one tackle. He was waived in April.

The 6-4, 212-pound Williams signed with the 49ers as an undrafted rookie free agent out of the University of Houston in April.