"If the 49ers want to lighten Christian McCaffrey's workload, they must add a durable running back to the rotation," Moton wrote. "Robinson can grind out yards between the tackles, which would allow McCaffrey to stay fresh for the length of the regular season."

Christian McCaffrey had a forgettable season with the San Francisco 49ers last year. After missing the first half of the campaign due to a calf strain, the two-time All-Pro runnin