A former NFL Defensive Player of the Year, Harrison broke the bone around his eye against the Texans on Oct. 2.
"Worst case scenario, I'll be back after the bye for sure," Harrison wrote on his Facebook account.
The Steelers are severely banged up at linebacker since LaMarr Woodley could miss the game with a left hamstring injury and James Farrior may be out with a torn calf muscle.
It's a tough development for the Steelers (5-2) in a pivotal AFC North showdown against the Ravens (5-2).
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