Green-Ellis was Cincinnati's leading rusher each of the last two seasons. His role was reduced last year when Giovani Bernard was added to the backfield. Green-Ellis ran for 756 yards and a career-low 3.4 yards per carry. He was entering the final year on his contract.
The Bengals wanted another pass-catching threat out of the backfield. Hill carried 20 times for 90 yards and caught a team-high six passes for 70 yards during a 35-7 preseason win over Indianapolis on Thursday.
The Bengals also waived linebacker Brandon Joiner, defensive tackle LaKendrick Ross and quarterback Tyler Wilson on Friday.
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