The team signed veteran cornerback Marcus Williams to fill his roster spot.
“He’s invaluable,” Nagy told reporters. “That is a big loss for us, but Bryce is going to be part of the item once we go”
Callahan, the Bears’ nickelback, was replaced in Sunday’s game by Sherrick McManis.
Callahan had two interceptions, six passes defensed, two sacks and also 4 5 tackles in 13 games (10 starts) this season.