With the NFL's main free agency period now over and the 2014 Draft in the books, we can more accurately get a picture of projected NFL rosters and depth charts. We have a long way to go through training camp and preseason, obviously, but we can at least start to piece together where teams are strongest, deepest, most talented, and conversely where they're thin or threatened.

So far, I've looked at the NFL's best defensive lines and the best linebacker corps, and today I'm breaking down some of the league's best or most promising defensive secondaries.

I included 18 NFL clubs on my list today, all teams with the most realistic shot at being among the NFL's best in 2014. That said, I'm sure I overrated, underrated, or forgot about a couple teams with strong cornerback and safety talent and depth within my list. Here goes ...

(* indicates a free agent addition, italics indicates a rookie)

The elite

Seattle Seahawks

LCB Richard Sherman, FS Earl Thomas, SS Kam Chancellor, RCB Byron Maxwell, S Jeron Johnson, S Deshawn Shead, CB Jeremy Lane, CB Tharold Simon, CB Phillip Adams*, CB Akeem Auguste, CB AJ Jefferson*, CB/S Chandler Fenner, SS Terrance Parks*, CB/S Eric Pinkins, S Dion Bailey

The Seahawks' starting secondary is the best in the NFL, featuring three 2013 All-Pros in LCB Richard Sherman, FS Earl Thomas, and SS Kam Chancellor. Rounding out the group is Byron Maxwell, who took over at RCB for an injured-then-suspended Brandon Browner in Week 13 and proved he's no slouch himself. Successful secondaries work in concert with excellent front-seven play, of course, but Sherman, Thomas, Chancellor, and Maxwell executed Seattle's three-high scheme with efficiency and expertise, and they return all four in 2014.

Sherman was the least targeted cornerback in the NFL in 2013, but nonetheless led the league with eight interceptions, and per Pro Football Focus' tracking, held opposing quarterbacks to a league-low passer rating of 47.3 when he was targeted. Maxwell, who started five regular season games (and three playoff games, in which he played well), cannot be properly compared statistically to players with a full season, but in his relatively limited regular season action, held opposing quarterbacks to a 47.8 rating while picking off four passes. Kam Chancellor's primary role is as a box run defender, but when asked to play in coverage, displayed excellent route-recognition to blow up underneath crossing or combo routes.

The crux of Seattle's defense, though, is Earl Thomas, whose speed and quick route-recognition allows him to patrol the deep middle of the field alone. Despite being responsible for everything from the numbers-to-numbers (and slightly more), opposing teams only attempted 8 passes to Earl's area, the deep middle of the field, all season (first in the NFL), completing only two (first in the NFL).

In the slot, third-year corner Jeremy Lane, who has gathered some important experience over the past two seasons, figures in as the replacement to Walter Thurmond going forward.

New Orleans Saints

CB Champ Bailey*, S Kenny Vaccaro, S Jairus Byrd*, CB Keenan Lewis, CB Patrick Robinson, S Rafael Bush, S Marcus Ball, CB Corey White, CB Stanley Jean-Baptiste, S Vinnie Sunseri

The Saints' pass defense in 2013 was among the league's best - 6th per Football Outsiders DVOA metric, 8th per Pro Football Focus pass coverage grades, and held opponents to 194 yards passing per game (second) and 6.8 yards per attempt (ninth) on the year. These rankings illustrate the talent that New Olreans has patrolling the secondary.

Going into 2014, though, that secondary should be even better. The Saints will get their first round pick from last year in safety Kenny Vaccaro back off a broken leg and will pair him with big time free agent acquisition and 2013 All Pro Jairus Byrd, giving Rob Ryan a safety tandem to challenge Earl Thomas and Kam Chancellor as the best in the NFL.

Rob Ryan will have the benefit of a high-caliber safety tandem in Kenny Vaccaro and Jairus Byrd to utilize this season, Photo credit: Stacy Revere

Rafael Bush is an underrated talent at safety as well, particularly in coverage, which makes me wonder if a three-safety big-nickel look will be prominent for the Saints going forward. At cornerback, Keenan Lewis is another underrated player that held opposing quarterbacks to a 67.4 passer rating on the season while only missing one tackle in run support (per PFF).

The only missing (or questionable) piece to the Saints' secondary puzzle is what happens at the corner spot opposite Lewis. New Orleans signed Champ Bailey as the assumed starter or at least for a piece of veteran depth, and have some other contenders for the job in Corey White and Patrick Robinson. The decision to draft Nebraska's Stanley Jean-Baptiste, though, is an interesting one. Jean-Baptiste is a bigger cornerback best suited for press-man coverage on the outside, and could develop into a starter early in his career. He's obviously raw and may be limited in what he's asked to do early on, but if he can emerge as a solid cover corner with a set of well-defined responsibilities, the Saints will have themselves a complete secondary group.

Arizona Cardinals

LCB Patrick Peterson, SS Deone Buchanan, FS Tyrann Mathieu, RCB Antonio Cromartie*, CB Jerraud Powers, S Rashad Johnson, S Tony Jefferson, CB Justin Bethel

The Cards had an elite defense in 2013 and while their front seven got a lot of the fanfare, much of their success was attributable to a talented secondary. Patrick Peterson is one of the best cornerbacks in the game -- he's making noise of late with a public feud with Richard Sherman over who's the best -- and he'll now be paired with excellent free agent acquisition Antonio Cromartie, which gives the Cards one of the better cornerback duos in the NFL.

The Cards picked off 20 passes in 2013 while holding teams to 6.5 yards per attempt (fifth) and a 58.7 percent completion percentage (seventh), but probably gave up a little too much in the passing game over the middle than they would have liked. To remedy this, Arizona used their first round pick to select Washington State's Deone Buchanan, and will likely throw him in early to join the versatile Honey Badger at safety.

The Cardinals already have some solid veteran depth there with Rashad Johnson, so in theory they can insert Buchanan into their defensive rotation while continuing to use Mathieu in a moveable-chess-piece role in the slot or all over their formations to further confuse and stymie offenses. Arizona's defense, especially in the secondary, will be fun to watch in 2014.

Cincinnati Bengals

CB Adam Jones, CB Terence Newman, CB Leon Hall, FS Reggie Nelson, SS George Iloka, SS Taylor Mays, CB Darqueze Dennard, CB Dre Kirkpatrick, S Danieal Manning*, S Shawn Williams, CB RJ Stanford, CB Lavelle Westbrooks

The Bengals featured an excellent pass defense in 2013 -- both Football Outsiders DVOA and Pro Football Focus' pass coverage metrics had them ranked fourth in the NFL -- and held opposing quarterbacks to a 74.2 rating (second), 5.9 yards per attempt (second), and a 59 percent completion rate (ninth).

Leon Hall will return after an Achilles injury last year, Photo credit: Timothy T. Ludwig-USA TODAY Sports Leon Hall will return after an Achilles injury last year, Photo credit: Timothy T. Ludwig-USA TODAY Sports

That was mostly without veteran Leon Hall though, who they return to the fold in 2014 after he suffered an early-season Achilles tear last year. Hall will re-join an already deep unit at cornerback that includes Adam Jones, Terence Newman, and Dre Kirkpatrick, and adding to the fun, first-round pick Darqueze Dennard will look to shake things up and secure a starting position as well. Cincy's cornerback group is also very versatile, so it will be interesting to see who they have playing on the outside and who they put inside in the slot. What's clear to me though is that this is a talented and deep group.

In the middle of the field, the Bengals added Danieal Manning to back-up veteran starter Reggie Nelson and the promising George Iloka at safety, and will look to sophomore Shawn Williams to grab hold of a bigger role. Taylor Mays, recently re-signed, has the ability to fit in as a safety but has been more effective in the box as a de facto linebacker.

The damn good

Buffalo Bills

LCB Leodis McKelvin, SS Aaron Williams, FS Da'Norris Searcy, RCB Stephon Gilmore, S Duke Williams, S Jonathan Meeks, CB Nickell Robey, CB Corey Graham, CB/S Ross Cockrell

The Bills -- and maybe this is just a function of finishing last in the AFC East -- seem to really have an underrated defense. Their pass defense in particular failed to receive the attention it deserved, finishing second in Football Outsiders DVOA in 2013, 5th in Pro Football Focus' pass coverage tracking, and they held opposing quarterbacks to a 55.3 percent completion rate. The Bills picked off 23 passes and held opposing quarterbacks to a 74.9 passer rating, both good for second in the league, respectively. Needless to say, when paired with their excellent pass rush up front, this Bills' secondary is doing their job.

The Bills seem to really have an underrated defense.

Of course, the Bills lost Jairus Byrd in free agency to the aforementioned Saints, so that's obviously a pretty huge question mark. But, while Da'Norris Searcy is the one to watch going forward, he definitely has excellent support in Leodis McKelvin (held opposing QBs to a 66.3 passer rating when targeted per PFF) and Stephon Gilmore (72.1 passer rating when targeted) on the outside, and strong safety Aaron Williams on the inside.

Williams ended last year on a strong note and secured a four-year, $26M deal, and the Bills recently signed veteran corner Corey Graham to a four-year $16M contract. Graham has experience on the outside and in the slot, but could be another candidate to make the move, like Williams previously did, from cornerback to safety, in 2014.

Add in Duke Williams and Jonathan Meeks into the mix as versatile defensive backs capable of playing in the slot or at safety, Nickell Robey as an exciting slot cornerback option, and rookie draft pick Ross Cockrell as another inside-outside threat, and this is a very talented Bills group.

The revamped

This group is an interesting one, and don't let its placement fool you. Any one of these teams could join the ranks of the elite in 2014 but their secondaries have been revamped at the most key, important starter positions, so it's a bit of a projection as to how things will shake out in respective schemes. So, in other words, these teams look awesome on paper - elite, even - but don't have the same experience together as a unit, in a familiar system, as some of the teams listed above.

New England Patriots

CB Darrelle Revis*, SS Duron Harmon, FS Devin McCourty, CB Brandon Browner*, CB Logan Ryan, CB Alfonzo Dennard, CB Kyle Arrington, S Tavon Wilson, SS Kanorris Davis, SS Patrick Chung, S Jemea Thomas

The Patriots defensive secondary is one of the most interesting groups of 2014, as far as I'm concerned, and the addition of Darrelle Revis is obviously the main story. It's not totally clear how things will shake out in Bill Belichick's scheme for this year, but with Revis at LCB, the Patriots may try to run a Seattle-style single high look, shading coverage over to the right side of the field and relying on Darrelle to do what he always does and shut down his side.

At the right cornerback spot, once his suspension is up, we could see Brandon Browner playing in press up at the line and receiving help over the top from All Pro safety Devin McCourty, Duron Harmon, or perhaps interestingly Logan Ryan. Ryan, who played corner in his first season, may get the nod as a free safety, which would move McCourty to the strong side. Regardless, whether it's a two-high shell or cover-3 look, the Patriots are greatly upgraded in the secondary, and the talent Revis possesses allows them to do some very interesting things schematically.

As for depth, Kyle Arrington is an intriguing option in the slot and Alfonzo Dennard will look to continue developing.

Denver Broncos

LCB Aqib Talib*, SS TJ Ward*, FS Rahim Moore, RCB Bradley Roby, CB Kayvon Webster, S Quinton Carter, S Duke Ihenacho, CB Chris Harris, CB Tony Carter, S Omar Bolden, S David Bruton, CB Jerome Murphy

this is a nice starting unit of five, with elite potential.

The Broncos got 2013 All Pro corner Aqib Talib in free agency, and provided he can stay healthy, he should provide them a lock-down type of option on the outside. They added to their free agent class with a nice pickup in strong safety T.J. Ward, a hard-hitter that does his best work in the box defending the run but is still quite capable in pass coverage. They bolstered this group with their selection of the high-ceiling but inconsistent Bradley Roby out of Ohio State, who figures to come in and start from day one (though that's not a given).

With Rahim Moore at free safety and Chris Harris either in the slot or outside, this is a nice starting unit of five, with elite potential. Futher, there's solid depth there, with safety Duke Ihenacho, safety Omar Bolden, and corner Keyvon Webster in the mix.

New York Giants

CB Dominique Rodgers-Cromartie*, SS Antrel Rolle, FS Quintin Demps*, CB Prince Amukamara, CB Walter Thurmond*, S Nat Berhe, S Stevie Brown, CB Jayron Hosley, SS Cooper Taylor, CB Zack Bowman, CB Travis Howard, CB Trumaine McBride

The Giants had an underrated defensive secondary in 2013 and added three players in free agency that should make an immediate impact: Dominique Rodgers-Cromartie, Quintin Demps, and Walter Thurmond. Rodgers-Cromartie will play on the outside, Demps at free safety, and it's likely that Thurmond will come in to play inside at the nickel spot, his specialty in Seattle. Antrel Rolle comes off of an All Pro 2013 season, Trumaine McBride emerged, Prince Amukamara's ceiling remains high, Stevie Brown is back off an injury, and Jayron Hosley is an interesting sleeper to contribute either inside or out. Nat Berhe is an interesting pick and could play a sub-package role early in his career, and it will be interesting to see if Cooper Taylor can carve out a niche for himself in his sophomore season.

Overall it's a very deep group.

The wild cards

Like the revamped teams above, any of these wild card teams have the potential to leap their way into the elite category. They're in this group because in my view, there are still a few uncertainties to sort out with regards to player development, and some will be relying fairly heavily on rookies early on, which is always... well, a wild card.

Cleveland Browns

CB Joe Haden, SS Donte Whitner*, FS Tashaun Gipson, RCB Justin Gilbert, CB Pierre Desir, CB Buster Skrine, S Jordan Poyer, CB Leon McFadden, CB Isaiah Trufant, S Jamoris Slaughter, S Darwin Cook, S Johnson Bademosi

I like this Browns secondary a lot. Joe Haden is an All Pro shutdown cornerback, Donte Whitner is a proven enforcer at strong safety, and Tashaun Gipson intercepted five passes last year at free safety. Cleveland used one of their first-round picks on Justin Gilbert, and it seems likely that we'll see him starting opposite Haden. Leon McFadden, Isaiah Trufant, and Buster Skrine provide some experienced depth, and Pierre Desir is an interesting small-school pick that could surprise some people early on.

Whitner thinks that this group can be counted among the elite in 2014 - and it will be interesting to see if this materializes.

San Francisco 49ers

CB Tramaine Brock, SS Antoine Bethea, FS Eric Reid, S/CB Jimmie Ward, CB Chris Culliver, S C.J. Spillman, S/CB Dontae Johnson, CB Perrish Cox, CB Chris Cook, CB Eric Wright, CB Darryl Morris, S Craig Dahl, CB Keith Reaser, CB Kenneth Acker

The Niners had, and probably will continue to have, one of the best pass defenses in the NFL, but it's going to be a different group than the elites they fielded in 2013. After letting three of four defensive secondary "starters" from last year -- Tarell Brown, Carlos Rogers, and Donte Whitner -- go free agency, there's some shuffling to do before the new starters emerge. As you'd expect, though, San Francisco does have solid depth to work with for this.

A look at how the 49ers will use Jimmie Ward

Tramaine Brock and Chris Culliver both are very experienced in the Niners' scheme and Perrish Cox showed promise in the slot late last year. Antoine Bethea ostensibly replaces Whitner as a starter at strong safety, and Eric Wright and Chris Cook are guys that factor in as experienced vets.

Using their incredible ammunition, San Francisco also went to town on the defensive secondary in the 2014 Draft. Jimmie Ward and Dontae Johnson are two extremely interesting picks for San Francisco, and Ward in particular figures to contribute heavily immediately as a slot cornerback/safety hybrid. Pairing Ward with Eric Reid is going to be one of the most interesting schematic dynamics to watch this year, and the two figure to be counted among the top echelon of safety pairings looking further down the line.

Tampa Bay Buccaneers

LCB Alterraun Verner, SS Mark Barron, FS Dashon Goldson, RCB Johnthan Banks, CB Mike Jenkins, S Major Wright, S Kelcie McCray, CB Leonard Johnson, DJ Moore, CB Rashaan Melvin, CB Deveron Carr, CB Danny Gorrer

The Bucs lost Darrelle Revis, which obviously hurts, but signed one of the more underrated All Pro players last year in Alterraun Verner to replace him. Verner will play opposite Johnthan Banks, who struggled at times his rookie season but still possesses a high ceiling. Putting Banks in Lovie Smith's Tampa-2 defense is an interesting prospect for the Bucs as well. Patrolling the middle of the field are Mark Barron and Dashon Goldson - Barron the Bucs 2012 1st round pick and Goldson a 2012 All Pro safety.

The Bucs also have some nice depth. Leonard Johnson and DJ Moore will compete in the slot, and Mike Jenkins and Major Wright provide some veteran depth. Rashaan Melvin returns from the injured reserve and will battle for a role as an outside cornerback. 2013 may have been down for the Bucs in general, but their defensive secondary has the talent to really excel in Lovie Smith's scheme.

Miami Dolphins

CB Brent Grimes, SS Reshad Jones, FS Jimmy Wilson, CB Cortland Finnegan, CB Will Davis, CB Jamar Taylor, S Jordan Kovacs, S Louis Delmas, CB Walt Aikens, S Don Jones

The Dolphins had one of the more underrated defensive secondaries last year and while they lost a few key pieces to that, their future looks bright if a few key players can develop. With Brent Grimes holding things down mostly at left cornerback, Will Davis, Jamar Taylor, and perhaps rookie Walt Aikens will battle it out with veteran Cortland Finnegan for the right corner starting spot. Davis and Taylor in particular project to be big time factors in Miami's secondary, but as the category suggests, their development is a wild card.

Contenders

Kansas City Chiefs

CB Sean Smith, FS Husain Abdullah, FS Eric Berry, CB Brandon Flowers, CB Chris Owens, CB Sanders Commings, CB Ron Parker, CB Phillip Gaines, SS Daniel Sorensen, FS Bronson Malcolm, S Jeron McMillian, CB Demarcus Van Dyke

It's hard not to like the talent in the Chiefs' secondary with Sean Smith, Husain Abdullah, Eric Berry, and Brandon Flowers, and Sanders Commings is a very interesting developmental player as well. The Chiefs also went out and added Phillip Gaines and Daniel Sorensen in the draft to provide some needed depth and competition in that area. This should be an improved group in 2014.

Green Bay Packers

LCB Tramon Williams, SS Morgan Burnett, FS Ha-Ha Clinton-Dix, RCB Sam Shields, CB Casey Hayward, CB Davon House, SS Chris Banjo, FS Micah Hyde, CB Jarrett Bush, CB Demetri Goodson

The Packers have some talent at the cornerback position in Williams, Shields, and Hayward, and added a guy that many believed was the top safety in this year's class in Ha-Ha Clinton-Dix. With further improvement from House, Hyde, and Bush, plus a contribution from rookie Demetri Goodson, the Packers could really move up in the pass defense rankings and have one of the more talented units in the NFL.

Oakland Raiders

CB DJ Hayden, SS Tyvon Branch, FS Charles Woodson*, CB Tarrell Brown*, CB Carlos Rogers*, S Usama Young, CB Taiwan Jones, CB Chimdi Chekwa, CB Travis Carrie, FS Jonathan Dowling, CB Keith McGill, CB Neiko Thorpe

The Raiders have quietly built a pretty interesting secondary with a combination free agency and the Draft. Hayden looks to blow up his sophomore season after being the Raiders' surprise first round pick last year, and Woodson, Brown, and Rogers add some much needed talent and experience to the group. I liked the trio of rookies that Reggie McKenzie acquired in the big, physical McGill, the underrated playmaker in Carrie, and the former Florida transfer in Dowling. It should be fun to see how improved the Raiders are in the back end this year.

As I said last week, I'm not going to pretend I got all these into the correct groupings, and I'm sure I left a few candidates off the list, so in the comments below, let me know where you differ in opinion or let me know where I missed the mark.