The Buffalo Bills have had to sustain several injuries on offense with LeSean McCoy and Sammy Watkins as the biggest names, but a new injury has created some questions.

Rookie running back Karlos Williams suffered a concussion on Sunday and is considered day-to-day, with his status for Week 5 uncertain. In wake of the latest injury at running back, the Bills are reportedly working out former first-round pick, Trent Richardson on Tuesday.

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According to NFL insider Ian Rapoport, the Bills are also working out a handful of other unnamed running backs Tuesday, but Richardson is the most notable. Boom Herron is also on the list of backs working out for the Bills.

Richardson last played for the Oakland Raiders before being cut by the team in August. He's averaged just 3.3 yards per carry in his career and hasn't panned out as the No. 3 overall pick in 2013.

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