The injury occurred in the 3rd quarter of Thursday night's loss to the Browns. Manuel was scrambling when Browns defensive back Tashaun Gipson drilled Manuel in the knee. Manuel left the game and did not return.
Bills running back Fred Jackson sustained the same injury last year during the season opener and missed the next two games.
Marrone said the Bills would investigate bringing in another quarterback, with only Jeff Tuel and practice squadder Thad Lewis as healthy QBs on the roster. He added "it would not be a stretch" that a new QB could be the starter in the Bills' next game against the Bengals.
Otherwise, the Bills mostly had good news on the injury front. Stevie Johnson's back injury should not prevent him from being on the field for Cincy game.
In addition, the secondary could get a huge boost. Safety Jairus Byrd will make his season debut at safety. Corners Stephon Gilmore and Ron Brooks have an excellent chance to join him in the lineup.
The Bills also cut punter Shawn Powell after just 18 games with the team. He had struggled most of this season. The Bills average net yards gained on punts this season was fourth from the bottom in the NFL.
Marrone did not comment on a who may be the replacement punter.
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