McKinnon had surgery on Tuesday. The tear was "pretty clean," according to a report from Matt Maiocco of NBC Sports Bay Area. The running back tweeted the following on Wednesday.
While McKinnon sets off on the road to recovery, the 49ers entered the season with Alfred Morris and Matt Breida trying to carry his anticipated workload. Breida gained 46 yards against the Vikings defense while Morris managed to add 38. The 49ers lost the season opener 24-16.