Hillis, who rejuvenated the Broncos' banged-up backfield since moving over from fullback last month, is the sixth tailback to go down for Denver this season. He was replaced by Tatum Bell, who was signed last month.
Hillis was hurt when he went up high for a pass from Jay Cutler and was hit by two defenders as he came down with the 11-yard reception at the Chiefs 34. He walked gingerly off the field after staying down a minute.
The Broncos have four tailbacks on IR -- Michael Pittman, Anthony Alridge, Andre Hall and Ryan Torain -- and Selvin Young (groin) has just one carry in the past two months.
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