San Francisco 49ers star running back Christian McCaffrey did not practice during Monday's training camp session. The San Francisco 49ers are currently taking part in training camp as they gear up to kick off their preseason slate later this week. On Monday, the team got a concerning update regarding star running back Christian McCaffrey. “Christian McCaffrey is sitting out practice today with what the team describes as ‘tightness,'” reported Matt Maiocco of NBC Sports Bay Area on X, formerly Twitter. The 49ers are set to kick off their regular season in exactly one month with a tough test against the Los Angeles Rams in Australia.