The Steelers now are as thin as the Cowboys at edge rusher.
They began the night without Alex Highsmith, who is inactive with a groin injury. They lost Nick Herbig with a hamstring injury in the third quarter.
Now, they have lost DeMarvin Leal, who is doubtful to return with a stinger.
Leal was injured with 10:55 remaining, leaving the Steelers with T.J. Watt and Jeremiah Moon as their only healthy outside linebackers.
Leal has one tackle.
The Cowboys began the night without DeMarcus Lawrence, Sam Williams and Micah Parsons and lost Marshawn Kneeland to a knee injury on the first drive.