The Sports Xchange

By Frank Cooney, The Sports Xchange

EditorsNote: Updates headline to Boom NFL Analysis: Legion of Boom best DB group

When it comes to determining the best defensive secondary in the NFL, there is little reason for discussion. The title belongs to the Seattle Seahawks' Legion of Boom.

Still, Legion leader Richard Sherman will be happy to discuss the issue -- or any issue -- including why he should be considered the best cornerback in the league, which he may well be, although Arizona's Patrick Peterson begs to differ and New England's vagabond Darrelle Revis insists he still has game.

The Seahawks' rough, ready and rowdy group features two first team All-Pros in Sherman as the monstrous mugger (listed at 6-foot-3, 195 pounds but admits to being well over 200) at left corner and Earl Thomas as the free safety who hoards more real estate than Donald Trump. Add hard hitting strong safety Kam Chancellor and right corner Byron Maxwell and you have the key to a defense that led the league in scoring defense and gave up only 203.1 yards passing per game.

Maxwell, the newcomer on the Legion, which adopted that name in 2012, played so well last season that the Seahawks were comfortable enough to let former starter Brandon Browner and nickel back Walter Thurmond go in the offseason. Jeremy Lane is expected to fill the nickel back position.

Those who somehow didn't know about Sherman before last year's NFC Championship Game, certainly remember he was the guy involved in breaking up the San Francisco 49ers' last-chance pass to Michael Crabtree and then ranted about the play on national television.

But as much as he talks -- which is considerable -- Sherman backs it up with his play on the field.

At some point during all the raving about Sherman in the offseason, Peterson, the multi-talented cornerback at Arizona, claimed that he is better because he covers the best opposing receiver regardless of where that receiver lines up, whereas Sherman stays on the defensive left side. Revis, of Revis Island fame, says ditto.

After being considered the best corner in the game before blowing out his knee with the New York Jets in 2012, Revis played close to his best last year at Tampa Bay before jumping to the Patriots this year, where he will team with one of the league's top safeties, Devin McCourty.

Here is a closer look and analysis of every defensive secondary unit by Sports Xchange reporters who cover each team:

SEATTLE SEAHAWKS

--DEFENSIVE BACKS: Starters -- LCB Richard Sherman, RCB Byron Maxwell, FS Earl Thomas, SS Kam Chancellor. Backups -- CB Jeremy Lane, CB/S Deshawn Shead, CB Tharold Simon, CB Phillip Adams, CB A.J. Jefferson, CB Akeem Auguste, CB Chandler Fenner, SS Jeron Johnson, SS Dion Bailey, FS Terrance Parks, FS Eric Pinkins.

One of the Seahawks' major offseason objectives was to extend Sherman and Thomas. Mission accomplished, and Seattle now has the bulk of the Legion of Boom -- Sherman, Thomas and Chancellor -- under contract through 2017. Those three also rank as among the best at their positions in the NFL and the strength of the Seattle defense. Thomas has rare speed and awareness to play deeper than many safeties, and makes it hard for offenses to get big plays on the Seahawks. Sherman has shown he can back up all his talk. Chancellor doesn't talk much, but speaks loudly on the field, as Denver's Demaryius Thomas found out when he was laid out early by a Chancellor hit that set the tone for the Super Bowl. Seattle let Walter Thurmond and Brandon Browner go in the offseason but wasn't worried due to the late-season emergence of Maxwell, whose 6-foot-1, 207-pound size fits the Seattle big-corner prototype. Lane projects as the starting nickel to replace Thurmond, who signed with the Giants. Lane played extensively down the stretch, quelling any fears about his readiness to step into a major role this season. Simon, a fifth-round pick in 2013 who sat out last year due to injuries, was one of the offseason stars and could become the backup outside corner. The team is also high on Jefferson, who spent the last four years with the Vikings and could also help in the return game. Shead is valued for his versatility, which could earn him a roster spot as a backup at just about every spot. Johnson projects as the backup to Chancellor, but needs to stay healthy. Parks was a revelation during the offseason and could also become a backup safety. Pinkins, the team's sixth-round pick in 2014, was drafted as a corner but is playing now at safety.

DEFENSIVE BACKS

ARIZONA CARDINALS

--DEFENSIVE BACKS: Starters - CB Patrick Peterson, CB Antonio Cromartie, FS Tyrann Mathieu, SS Deone Bucannon. Backups -- S Rashad Johnson, S Curtis Taylor, S Tony Jefferson, CB Jerraud Powers, CB Justin Bethel, CB Bryan McCann.

Peterson covered the best receiver every week. He's an elite player but he can improve. Signing Cromartie gives coordinator Bowles the option of keeping each of his corners on one side of the field. Powers is smart and physical and will be the nickel corner until Mathieu returns from a knee injury. Johnson lost his job to Mathieu midway through the season. Mathieu is instinctive and makes a lot of plays. Johnson is smart and does a nice job of getting teammates lined up correctly. There won't be much of a drop-off is he is the starter while Mathieu is out. Bucannon, the first-round pick, has a reputation as a big hitter. Coverage is his biggest question.