Gibson isn't present for the open portion of Wednesday's practice, Nicki Jhabvala of The Washington Post reports.
Head coach Ron Rivera said Tuesday that Gibson is dealing with a sprain, but he didn't offer any further details about the running back's injury. Gibson will have two more chances to increase his practice activity ahead of Sunday's matchup against the Browns, but if he can't go this weekend or ends up being limited, Jonathan Williams would be in line to handle more work behind Brian Robinson.