49ers coach Jim Harbaugh revealed second-year RB Marcus Lattimore is "working through something" and will not take part in rookie minicamp. Lattimore is eligible for rookie camp despite not technically being a rookie because he spent all of 2013 on the reserve/non-football injury list. Harbaugh did not disclose what is bothering Lattimore, but said it's not related to his balky knees. We're not counting on Lattimore to be a major 2014 contributor. The 49ers' second-round pick of Carlos Hyde suggests they aren't, either.