AP

On Monday, the Bills announced that rookie running back Karlos Williams was hospitalized after waking up “in a lot of pain” but didn’t disclose exactly what was bothering Williams.

There’s still no word about the specific ailment, but it looks like the rookie is going to be out for a while. Tyler Dunne of the Buffalo News reports, via a source, that the injury is “serious” and that Williams will miss multiple weeks while he recovers.

Williams’s injury adds to the injury woes that have thinned out a position of strength for the Bills over the last few weeks. Anthony Dixon has been out with a calf injury and hamstring woes have sidelined Fred Jackson and Bryce Brown, which left the team with LeSean McCoy and Bronson Hill as their healthy backs heading into Tuesday’s practice.

They remedied that by signing Ricky Seale, who ran the ball 34 times over his final two seasons at Stanford.