McCormick rushed six times for 53 yards and a touchdown in Thursday night's 41-17 preseason win over the Chargers.
McCormick was the 49ers' leading rusher in the contest despite receiving fewer attempts than Kaelon Black or Zamir White. The running back is currently competing with Black and White to be a potential backup to Christian McCaffrey (undisclosed) while Jordan James (ribs) and Isaac Guerendo (pectoral) are sidelined with injuries.