San Francisco 49ers head coach Kyle Shanahan discussed new running back Brian Robinson Jr. on Sunday, saying the former Washington Commanders ' starting back would be Christian McCaffrey's backup.

Brian Robinson Jr., in his 49ers practice debut, rotated in with Christian McCaffrey in an hour-long, no-pads practice.

General manager Adam Peters, who came from San Francisco, drafted Jacory Croskey-Merritt in the seventh round this year, and the rookie known as “Bill” was expected to share carries with Austin Ekeler and Chris Rodriguez Jr. after Robinson appeared to fall out of favor with the coaching staff.