ORCHARD PARK, N.Y. (AP) The Buffalo Bills signed free agent running back Dan Herron to address an injury-depleted backfield that could be down yet another player.
Herron signed on Tuesday after being one of several running backs to work out try out for the job at the team's facility.
Buffalo is suddenly short on running backs after general manager Doug Whaley announced rookie Karlos Williams' status is uncertain after he sustained a concussion in a 24-10 loss to the New York Giants.
Speaking on his weekly radio show on WGR-AM, Whaley said Williams was tested for a concussion on Monday after he complained of not feeling well following the game. In his first career start, Williams had 30 yards rushing and scored on a 23-yard catch filling in for LeSean McCoy, who's out indefinitely with a left hamstring injury.
Williams leads the team with 226 yards rushing, and has scored a touchdown in each of Buffalo's four games. He is following the NFL's concussion protocol, and must pass a series of tests before being cleared to play.
Buffalo (2-2), which plays at Tennessee (1-2) on Sunday, has only two other running backs on its roster: backup Boobie Dixon and rookie Cierre Wood, as well as fullback Jerome Felton.
Dixon has no yards on eight carries this season. Wood was promoted from the practice squad last week and had a catch for minus-6 yards against the Giants.
Herron spent the previous two seasons in Indianapolis, where he had 389 yards rushing and a touchdown in 25 games, including three starts. The Colts released Herron last month by placing him on waived-injured.
Selected in the sixth round of the 2012 draft by Cincinnati, Herron spent a little over a season with the Bengals before being signed by the Colts.
The Bills are scrambling for running backs after they had a glut of them during training camp. Veteran Fred Jackson was cut in August, and then signed with Seattle. Buffalo also released Bryce Brown a week into the season to open a roster spot after defensive tackle Marcell Dareus returned from serving a one-game NFL suspension.
The Bills also placed reserve tight end MarQueis Gray on the season-ending injured reserve list after he broke his forearm on Sunday. Buffalo also signed receiver Walter Powell to its practice squad.
In signing with Buffalo, Herron beat out several other contenders who worked out for the job, including Trent Richardson and Alfonso Smith.
A person familiar with the situation told The Associated Press that Richardson and Smith also worked out for the Bills. The person spoke on the condition of anonymity because the Bills did not reveal what players they brought in for workouts.
It's the second time Herron has had the edge on Richardson, who was selected with the third pick in the 2012 draft by Cleveland. After a solid rookie season, Richardson was traded to Indianapolis, where he eventually lost the starting job to Herron.
Richardson was waived by the Colts in March.
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