McKinnon, who is dealing with soreness in his knee, is slated to receive a platelet rich plasma injection, Nick Wagoner of ESPN.com reports.
Wagoner adds that coach Kyle Shanahan relayed that McKinnon -- who tore his right ACL last Sept. 1 -- could potentially be back at practice in a couple of weeks, but the team's prime goal and hope is to have the running back ready for Week 1. Per Matt Maiocco of NBC Sports Bay Area, McKinnon can't go back on the team's PUP list, so if he's "slow to recover, the only option would be to start season on IR and come back later in the season." That's something the team would prefer to avoid, but Shanahan added that if if McKinnon isn't recovered by the start of the season, "we'll be patient with him." For now, Matt Breida and Tevin Coleman are the team's top two healthy backs.