'The Bills' defense has shown a propensity to struggle when it comes to switching players in and out of the lineup to accommodate various defensive looks and anticipated offensive formations. The Eagles' offense is designed to make such substituting difficult, if not impossible, and causes the defense to risk being caught short of a player or two or penalized. It won't be easy, but Buffalo's scout team must do the very best job possible replicating the up-tempo approach of Kelly's offensive scheme.'