NFL

Bills GM says running back Williams sustained concussion

ORCHARD PARK, N.Y. (AP) The Buffalo Bills' depth at running back could be further depleted after tests revealed rookie Karlos Williams sustained a concussion.

General manager Doug Whaley revealed Williams' injury Tuesday during his radio show on Buffalo's WGR-AM. Whaley says tests showed the concussion on Monday, a day after Williams complained of not feeling well following a 24-10 loss to the New York Giants.

Williams is following the NFL's concussion protocol, and must pass a series of tests before being cleared to play. Buffalo (2-2) plays at Tennessee (1-2) on Sunday.

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Williams was hurt after making his first start filling in for LeSean McCoy, who is out indefinitely because of a hamstring injury.

The Bills have only two other running backs on their roster, Boobie Dixon and Cierre Wood, plus fullback Jerome Felton.

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