Here’s a quick look at the top three positional needs for the Buffalo Bills:
Defensive end: The Bills are expected to release Mario Williams this offseason, opening a hole at defensive end in Rex Ryan's scheme. The Bills will need a player who fits that role better than Williams. Ideally, it will be a player who is around 300 pounds and can stop the run consistently. They also could use a lighter player (about 250 to 270 pounds) to supplement Jerry Hughes as a pass-rusher.
Linebacker: With Nigel Bradham likely to sign elsewhere in free agency, the Bills need to fill his spot in the defense and potentially also find a middle linebacker to replace Preston Brown, who struggled in Ryan's defense this season. They have a handful of special-teams oriented players in Ty Powell, Tony Steward, Kevin Reddick and AJ Tarpley on their roster, but none is likely to slide into a starting role next season.
Offensive tackle: This is largely dependent on starting left tackle Cordy Glenn and his pending free agency. The Bills are expected to make re-signing Glenn a priority, but if he were to land elsewhere, left tackle immediately would become the Bills' top need. They also have some uncertainty at right tackle after Seantrel Henderson finished this season on the non-football illness list.