Evans, who didn't practice Monday, is tending to a minor quad strain, Ian Rapoport of NFL Network reports.
In a San Francisco receiving corps that already has lost Ricky Pearsall (knee, IR) for the season, Evans joined Christian Kirk (calf) and rookie second-rounder De'Zhaun Stribling (hamstring) on the sideline during Monday's session. Rapoport suggested the 49ers will give Evans a lighter workload until he's back to 100 percent, but in the meantime, Deebo Samuel will serve as the team's top available option at the position, while Demarcus Robinson, Jordan Watkins and Jacob Cowing should see more first-team reps.