Smith was injured in the second quarter and ruled out for the remainder of the game. He entered Wednesday listed as questionable because of back and ankle injuries.
The Ravens were already short-handed because of their COVID-19 outbreak. Baltimore has nine starters on the reserve/COVID-19 list.
Even without Smith, the Ravens' defense kept Baltimore close with the Steelers in the first half, holding Pittsburgh without a touchdown on three red zone drives.
In the third quarter, Baltimore starting cornerback Marcus Peters came off the field limping. It has been a rough season for the Ravens' defensive backfield, which has had five cornerbacks go on injured reserve.