Manning was limited in practice during the week by a strained right thigh and was listed as questionable. The Broncos (11-3) had clinched the AFC West and could earn a playoff bye with a win.
Marquis Flowers was starting at linebacker for the Bengals in place of Emmanuel Lamur, out with a hamstring injury. Eric Winston, signed three weeks ago, was expected to make his first start at right tackle.
Cincinnati (9-4-1) could clinch a fourth straight playoff berth with a win. Whoever wins the Bengals' game in Pittsburgh next Sunday night gets the AFC North title.