Bryce Callahan, Bears. At 5' 9" and 183 pounds, Callahan was undrafted in 2015, and had to ride the Bears' practice squad before he finally got a shot. When he did, he proved to be an integral part of Vic Fangio's defense with 18 receptions allowed on 31 slot targets. Had he played the entire season as opposed to making the field in fits and starts, there's no telling what he might have done. Callahan showed last year that is a very patient player who lets the plays come to him (which is unusual for a rookie). His lateral agility in short areas allows him to break off coverage and help when the play goes away from him. This is a player whose best is ahead of him. 

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