On Saturday, the Niners announced they've activated running back Tevin Coleman and cornerback K'Waun Williams off of injured reserve and both will be available to play against the Seahawks on Sunday.
In a corresponding move, the 49ers placed running back Jeff Wilson Jr. on injured reserve as he deals with a high left-ankle sprain. Wilson will miss at least the next three games, although coach Kyle Shanahan said earlier this week that he expected Wilson to miss about a month.
Coleman offers some needed depth at running back after battling a knee injury as the Niners have Wilson and starting running back Raheem Mostert on injured reserve with high ankle sprains. Coleman joins veteran Jerick McKinnon and rookie JaMycal Hasty as running backs available against the Seahawks.
Williams, who had knee and hip ailments, is expected to return to his usual role in the slot as the 49ers prepare to try to slow down Seahawks wideout Tyler Lockett and quarterback Russell Wilson. His return means the Niners will have three of their top four cornerbacks available for the first time in weeks as Richard Sherman remains on injured reserve with a calf issue.
In addition to activating Coleman and Williams, the 49ers also activated receiver River Cracraft and safety Johnathan Cyprien from the practice squad. Cracraft offers depth with receivers Deebo Samuel (hamstring) and Richie James Jr. (ankle) ruled out for Sunday and Cyprien does the same at strong safety as the Niners will again be without starter Jaquiski Tartt (groin).
James and Tartt were officially downgraded from doubtful to out on Saturday. Defensive lineman Kentavius Street (illness) was also downgraded from questionable to doubtful.