Gore sat out of practice on Tuesday for reasons that haven't been fully explained, although it has something to do with recovering from an injury.
Head coach Jim Harbaugh didn't explain exactly what that injury is or when it occurred, but did confirm it was a physical ailment that kept Gore sidelined. Per his presser:
"Just working through something. Nothing too serious."
The 49ers have had a bevy of injuries already this season and contact drills haven't even begun yet. San Francisco has been hit with a wave of issues, starting with the loss of wide receiver Michael Crabtree.
Crabtree tore his Achilles tendon last week and could be out anywhere from six months to the entire season.
In the meantime, Harbaugh is tinkering with the lineup, according to Niners Nation:
"He's a guard that can play tackle. He can play center. But, right now [T] Joe Staley's not practicing. He had a minor procedure done. So, Adam's getting some work at tackle, which he's got the ability to go guard, tackle, center. And we'll make sure that he's getting reps at all those."