49ers cornerback Ahkello Witherspoon was carted off during the fourth quarter of Sunday’s game in Pittsburgh.
The 49ers announced Witherspoon has a foot injury and is questionable to return.
Jason Verrett, active for the first time since arriving in San Francisco, replaced Witherspoon. Steelers quarterback Mason Rudolph targeted Verrett, who is playing his first game since the season opener in 2017, and officials flagged Verrett for a 32-yard pass interference penalty.
The Steelers scored on the next play with Diontae Johnson catching a 39-yard pass from Rudolph to give the Steelers a 20-17 lead with 10:22 remaining.