Weakest safety group: Tampa Bay Buccaneers
Lovie Smith has reunited with Chris Conte and Major Wright after watching the oft-injured safety duo get burned on a regular basis in Chicago. What makes him think the results will be different 1,200 miles south? D.J. Swearinger is a work in progress and needs to prove he cares more about tackling than hitting. A potential silver lining is Bradley McDougald, a former undrafted free agent who showed promising signs while stealing snaps from Dashon Goldson late last season.
The Giants' entire safety corps is unproven, led by second-round pick Landon Collins and a pair of recent late-round picks in Nat Berhe and Cooper Taylor. ... The Redskins signed Goldson and former Seahawks special teamer Jeron Johnson, but are they upgrades? Goldson is a major liability in coverage. Former Broncos castoff Duke Ihenacho is battling Johnson for the free safety job. ... Nate Allen's contract with the Raiders was one of the biggest head-scratchers of free agency. ... Shamarko Thomas is a question mark as Troy Polamalu's replacement in Pittsburgh. ... Calvin Pryor was a bust as the Jets' first-round pick last year.
Weakest cornerback group: New England Patriots
The Patriots' prowess in coaching up misfits shouldn't be underestimated, but that ability is going to be tested this season. Whereas New England boasted perhaps the NFL's best secondary a year ago, they are now forced to replace their top three cornerbacks with Darrelle Revis, Brandon Browner and Kyle Arrington out of the picture.
The Redskins blew more coverages than any secondary in the league last season. They desperately need Chris Culliver to play like he did in 2014 as opposed to the other three years of his career. ... D.J. Hayden and T.J. Carrie have shown flashes of promise, but consistency remains elusive. ... The Dolphins have a black hole behind Brent Grimes. ... The 49ers lost a pair of starters when Culliver and Perrish Cox walked out the door. ... If the Steelers are going to contend, they desperately need Antwon Blake and rookie Senquez Golson to emerge this season.
Weakest linebacker group: New York Giants
The linebackers have never been asked to do the heavy lifting on the defenses of the Tom Coughlin era. The disruption starts up-front with the defensive line instead.
This year's unit is heavily reliant upon middle linebacker Jon Beason, who simply can't stay healthy for 16 games. J.T. Thomas, a former special teamer in Jacksonville and Chicago, is penciled in on the weak side. Strong-side linebacker Devon Kennard, a fifth-round pick last year, showed intriguing pass-rushing potential once he hit the starting lineup in November.
The Cardinals' linebacker corps is riddled with question marks. Sean Weatherspoon and LaMarr Woodley have been injured and/or ineffective the past couple of years. Bruce Arians can't count on Daryl Washington to save this unit. ... Outside of free-agent acquisition Pernell McPhee, the Bears have a host of linebackers better suited for their old 4-3 defense. ... The Falcons lack impact players at the position. ... The Chargers are the rare 3-4 defense incapable of generating a pass rush. ... The Bengals' linebacker corps isn't the same without Vontaze Burfict, a candidate to start the season on the PUP list. ... The Saints identified the position as a weakness, picking up veteran Dannell Ellerbe and a pair of early-round draft picks.
Weakest defensive line (3-4) group: Chicago Bears
The Bears were counting on the recently-released defensive end Ray McDonald to play a major role in new coordinator Vic Fangio's transition to a 3-4 scheme. Now they have to rely upon second-year players Will Sutton and Ego Ferguson, both of whom were drafted to play defensive tackle in Mel Tucker's 4-3 defense.
The 49ers must replace more than 50 percent of their snaps up front following the departures of McDonald and Justin Smith. ... Arthur Jones and Kendall Langford are solid starters on paper, but the Colts aren't going to get the benefit of the doubt until they hold the Patriots' ground attack under 150 yards and three scores. ... The Titans have little to boast beyond Jurrell Casey, who recently made his overdue debut on NFL Network's Top 100 Players list. ... Until 2014 second-round pick Stephon Tuitt emerges as a solid starter, the Steelers' line will remain vulnerable against the run.
Weakest defensive line (4-3) group: Oakland Raiders
Who carries this group when the best player is a past-his-prime Justin Tuck? Free-agent pickup Dan Williams has been a run-stuffing nose tackle. Will he be tasked with penetrating opposing offensive lines as a 4-3 defensive tackle in Oakland? A lot will be asked of second-round defensive end Mario Edwards Jr., whose motor was questioned coming out of Florida State.
This front is ostensibly set up to play smashmouth, smothering run defense. How will they manufacture heat on opposing quarterbacks?
It speaks to the weakness of the other three spots that the Bucs made this list with Gerald McCoy, one of the NFL's most disruptive three-technique defensive tackles. ... The Falcons need a year or two to adjust to Dan Quinn's 4-3 scheme after acquiring Paul Soliai, Tyson Jackson and Ra'Shede Hageman to provide more 3-4 looks last year. This offseason's pickups -- O'Brien Schofield and Adrian Clayborn -- have managed a paltry three sacks per season.