With free agency set to kick off at 4 p.m. ET on Tuesday, March 11, Elliot Harrison identifies needs for all 32 teams over eight divisional primers. Click on each division for full analysis:
» Chicago Bears: Downtrodden defense badly needs safety help.
» Detroit Lions: Still seeking a Calvin Johnson complement at WR.
» Green Bay Packers: Defensive line issues abound in Titletown.
» Minnesota Vikings: Who can play linebacker for Mike Zimmer?
» Baltimore Ravens: Joe Flacco certainly could use more weapons.
» Cincinnati Bengals: Stout D remains underwhelming in one area.
» Cleveland Browns: Whole lotta needs, whole lotta spending cash.
» Pittsburgh Steelers: Troy Polamalu and the troubling old guard.
» Atlanta Falcons: This defense simply must boost its sack total.
» Carolina Panthers: Protecting Cam Newton is a major concern.
» New Orleans Saints: The secondary is rife with question marks.
» Tampa Bay Buccaneers: Lovie Smith inherits a D with one flaw.
» Houston Texans: Time to protect J.J. Watt on the defensive line.
» Indianapolis Colts: Back end of D looms as a playoff problem.
» Jacksonville Jaguars: Desperately seeking sacks (per usual).
» Tennessee Titans: GM Ruston Webster remains a mystery man.
» Dallas Cowboys: Tight cap could limit Jerry Jones' activity.
» New York Giants: No-name linebacking corps really stands out.
» Philadelphia Eagles: Chip Kelly has a glaring need on defense.
» Washington Redskins: Last line of defense is quite unsettling.
» Buffalo Bills: Transitioning defense lacks linebacker depth.
» Miami Dolphins: Ryan Tannehill's safety must be prioritized.
» New England Patriots: Vince Wilfork needs younger colleagues.
» New York Jets: Is this Michael Vick's ultimate destination?
Nix had arthroscopic knee surgery Thursday, and his season is over. He has been bothered by knee tendinitis this season and missed two games.
Follow Elliot Harrison on Twitter @HarrisonNFL.