Brooks has been diagnosed with a concussion and will not return to Sunday's game against the Patriots, Jay Morrison of SI.com reports.
Brooks has entered the league's concussion protocol after being evaluated by medical staff and will not return. Practice squad running back Gary Brightwell will serve as Chase Brown's backup the rest of the way due to the absences of Brooks and Samaje Perine (ankle). Looking ahead, Brooks is in jeopardy of being sidelined for the Bengals' Thanksgiving Day clash against the Ravens.