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Richard Sherman is having a tremendous season. This may come as a shocking revelation during a week when the vulnerability of the Seahawks defense is the official big story.

Did you see Dez Bryant's 23-yard reception against Sherman to set up a touchdown? What about Bryant's jump ball over Sherman on 3rd-and-5 in the fourth quarter? Sherman needed pass interference to stop him on another series. What about Sherman's big mistakes in the Chargers loss? Face it: HE IS NOT A SHUTDOWN CORNERBACK.

Darrelle Revis is having a tremendous season. This may come as a shock after weeks of fretting about the downfall of the Patriots.

Did you see Sammy Watkins break him down for a 24-yard catch near the goal line Sunday? What about all the trouble he had against James Jones in the Raiders game? The guy has one interception and three passes defensed all year, for heaven's sake. Totally overrated. HE IS NOT A SHUTDOWN CORNERBACK.

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Patrick Peterson is having a very good season.

OK, wait. Timeout. Are you serious? He allowed two touchdowns against the Redskins! DeSean Jackson blew past him like a Mustang beating an ice cream truck off a red light. Every other Cardinals defender BUT Peterson had a great game Sunday. Face it: HE IS NOT A SHUTDOWN CORNERBACK.

Cue Inigo Montoya from The Princess Bride: "You keep using that word. I do not think it means what you think it means."

If your definition of "shutdown cornerback" is some magical superhero who never allows a reception and essentially constructs a 30-foot-high wall across one half of the field, then you are right: Sherman, Revis and Peterson are not shutdown cornerbacks.

If "shutdown cornerback" is just a defensive version of "elite quarterback," a sideswiping weapon in your everyone in the NFL is overrated arsenal, then no facts will get in the way of the story anyway.

But if you are looking for great cornerbacks, Pro Bowl-caliber cornerbacks, cornerbacks who influence opponents' strategy and cornerbacks who can make a major difference in the playoff race, then Sherman, Revis and Peterson fit the description.

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So here's a shocking revelation: The cornerbacks everyone says are great are, in fact, great. Even when they give up a touchdown, or their team loses a game.

For Cornerbacks, Non-Highlights Are Highlights

The Cowboys threw six passes to Richard Sherman's side of the field, according to my tally.

One pass resulted in an interference penalty. Two others were mentioned at the start of the article: 23- and 16-yard completions to Dez Bryant. Three others were incomplete passes to Bryant: a bomb where Sherman disrupted Bryant's pattern with a jam; tight coverage on a comeback route on 3rd-and-long; and a late-game sideline pass where Tony Romo had no window and forced his throw out of bounds.

So Bryant, one of the two or three best receivers in the NFL, caught two passes for 41 yards and forced one flag against Sherman. No other Cowboys wide receiver was thrown to with Sherman in coverage, though there were some passes into the flat in front of him.

As bad days go, Sherman's afternoon against Dallas was pretty darn good.

The Cowboys' big passing plays came against Byron Maxwell or nickel corner Marcus Burley, and of course they did their greatest damage on the ground. Bryant often lined up on the left side of the formation or in the slot to avoid Sherman early in the game. That's exactly what opponents are supposed to do against a great cornerback: adjust their game plans to avoid the dangerous defender.

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Revis allowed Watkins to catch just one meaningful pass Sunday; the rookie star was nearly invisible as the Bills did what little damage they could manage with Robert Woods and tight end Scott Chandler.

Peterson gave up a slant-and-go touchdown to Jackson and got rubbed on a touchdown to Pierre Garcon. They were the only significant plays he allowed all afternoon. Nickelback Jerraud Powers and safety Rashad Johnson combined for three interceptions and a forced fumble.

Ask yourself: Why were Powers and Johnson getting so many opportunities?

This is what great cornerbacks do. They funnel plays to other defenders by blanketing their receivers. They dissuade quarterbacks from throwing to their side of the field. And yes, sometimes they lose matchups to the likes of Dez Bryant or DeSean Jackson, whom they often draw in single coverage, or get victimized by a well-designed pick play.

It only takes a touchdown, a few receptions allowed or a poor team defensive performance for an All-Pro cornerback to attract criticism. Sherman brings much of it upon himself with his constant Twitter chirping. Revis has not been able to give up a catch for two years without every wise guy at the sports bar pointing at the screen.

You see that? He did it again! That was the third time I pointed Mr. Island Guy out this month!

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Peterson gets a break because the Cardinals go largely unnoticed by the world at large. But after Rueben Randle caught a one-handed back-of-the-end-zone fade when the Cardinals faced the Giants, color commentator John Lynch made sure to point Peterson out. "How about going right after Patrick Peterson, one of the finer corners in football?"

Later, when Peterson hooked Victor Cruz's shoulder to earn pass interference on otherwise outstanding deep coverage, the announcers chimed in again.

"The Giants go after their top corner again and succeed," Kevin Burkhardt said.

"Eli Manning told us in meetings that he would not shy away from Patrick Peterson...I don't think Peterson's used to it. He's used to people going the other way, and they're getting after him," added Lynch.

Cruz and Randle combined for nine catches, 99 yards and one highlight-reel touchdown in a 25-14 loss. Peterson allowed a few other short catches and drew two more contact fouls, but he must have been doing something right during all of those other plays when the announcers were not singling him out.

That's the problem with great cornerbacks: They are invisible when they succeed, unless the broadcasters assemble one of those "tight coverage" montages that are typically reserved for Revis. To really appreciate great cornerbacks, you have to scout them, keeping in mind that one-handed, leaping, sideline-tightrope catches are often evidence of great coverage, not bad coverage.

You can also look at the stats. Those, too, require a trained eye.

Numbers Never Lie but Are Often Very Quiet

The Seahawks had the best pass defense in the NFL against opponents' No. 1 wide receivers entering the Cowboys game, according to Football Outsiders. Opponents averaged just 6.7 pass attempts and 39 yards per game when throwing to their top targets. Bryant's four-catch performance will increase those numbers slightly. The Patriots rank ninth against top receivers, the Cardinals a surprising 19th.

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Sherman, of course, does not match up against opponents' top receivers all the time, nor does Peterson. Both play left cornerback, so they spend most of their time defending the offensive right side of the field. So we turn to NFL GSIS (a firewall site) to learn something about play directions.

Opponents have thrown 49 short passes to the right against the Seahawks, the third-lowest total in the NFL. They have thrown just 11 deep passes to Sherman's side, seventh in the NFL. Offenses tend to be somewhat right-handed—about 14 percent more passes are thrown to the left than to the right in a typical season—but not against the Seahawks.

Opponents have been quicker to challenge Peterson, in part because he now has Antonio Cromartie opposite him. But 16 deep passes to the right against the Cardinals have yielded just two completions. Again: Someone is doing something right.

For a more defender-centric approach, we turn to Pro Football Focus (subscription required). Sherman earns a green 3.5 "all is going well" score in their overall rankings, Revis a still-green 2.2, Peterson a dark crimson negative-4.1 reprimand, largely because of those penalties in the Giants game.

The meat of the Pro Football Focus defensive analysis does not lie with their red-green scouting data, which only counts plays the cornerback was directly involved in. Evaluating cornerbacks is all about negative space, the plays they didn't have to make, and those can be found on the far right sides of the PFF columns, where the number of times each defender was targeted are tabulated.

Sherman has been on the field for 353 snaps but has been targeted just 20 times. He is tied for the fewest targets in the NFL among defenders who have been on the field for 60 percent or more of their team's defensive snaps. Revis has been targeted 27 times in 367 snaps, tied for eighth lowest in the NFL with the Cardinals' Peterson (327 snaps) and Cromartie (319).

The "cornerbacks opponents avoid" list is full of other well-regarded defenders like Joe Haden, Sean Smith, Vontae Davis and Captain Munnerlyn, as well as up-and-comers like Desmond Trufant and veterans having good years on bad teams like Tarell Brown.

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Get the picture? Opponents really do avoid the top cornerbacks.

Go back to 2013, and you'll find Sherman and Revis last and second-from-last in times targeted among starters; Peterson sits near the middle of the pack, but with fine scouting ratings.

The most targeted starter last season was Jerraud Powers, who was in the crosshairs 122 times. Powers held his own as a starter in 2013 and has been a star as a nickel defender this year. A quick look at the whole stat sheet reveals why:

2014 Cornerback Statistics Player Snaps Targets Receptions Peterson 327 27 17 Cromartie 318 27 12 Powers 276 43 26 Pro Football Focus

Powers is intercepting passes because he is getting disproportionately targeted. Let's run the numbers for the Seahawks:

2014 Cornerback Statistics Player Snaps Targets Receptions Sherman 353 20 10 Maxwell 296 34 25 Burley 213 31 23 Pro Football Focus

The numbers are not as extreme for the Patriots, who have been juggling corners opposite Revis, but the trend is the same. Opponents are targeting the other cornerbacks. Powers has reaped a turnover bonanza, Burley and Maxwell have struggled, but the superstar cornerbacks have held up their end of the bargain.

Unfortunately, we needed three statistical outlets to help us tease the data. PFF buries the good stuff at the back of its tables, Football Outsiders provides opponent adjustments but few defender-by-defender breakdowns, and NFL GSIS is media-only.

You don't need a math degree to do the detective work that proves the NFL's best cornerbacks are as good as advertised, but it helps. Sometimes, your best bet is to just believe the hype, at least a little bit: The "experts" who proclaim players like Sherman and Revis to be All-Pro-caliber might actually know what they are talking about.

As for that "shutdown cornerback"? He never existed. Not even in the golden days of Prime Time.

Deion Sanders Was Not a Shutdown Cornerback

Once upon a time, there was a cornerback named Deion Sanders. He never gave up a reception, and any pass thrown to his side of the field was returned for a touchdown. Teams gave up throwing to their top receivers when they faced Sanders for an entire decade, making life incredibly easy for his teammates.

Sanders was, of course, a fabulous cornerback, one of the best in NFL history. He also played before NFL Game Rewind, Twitter or Bleacher Report, making it easier for his exploits to become folktales.

There was no Pro Football Focus or Football Outsiders back then to scour the game footage, but Football Outsiders has been collecting old play-by-play data for years. So we now have some statistical analysis of Sanders and the teams he played for.

Guess what? Sanders was not very different from Revis or Sherman at all.

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Sanders reached the Pro Bowl for the Falcons for the first time in 1991. He was then a Pro Bowler (typically All-Pro) every year until 1999 with the Cowboys, except for injury-shortened 1995.

Football Outsiders tabulated league pass defense rankings for those seasons; the numbers are far superior to raw passing yardage totals because they account for sacks, interceptions, completion rates and situational adjustments (like late drives in blowouts).

Here is where Sanders' teams ranked:

Team Pass Defense Rankings Year Team Pass Defense Rank 1992 Falcons 28th 1993 Falcons 27th 1994 49ers 3rd 1996 Cowboys 2nd 1997 Cowboys 17th 1998 Cowboys 27th 1999 Cowboys 12th Football Outsiders

Football Outsiders starts breaking down pass defense by opponent's targets in 1999, Sanders' last Pro Bowl season. The Cowboys ranked 25th in the league at stopping No. 1 receivers, allowing an adjusted 73.1 yards per game. Assuming Sanders' fade was gradual (nagging injuries had been limiting him for years), Dallas stopped ranking in the top five at stopping No. 1 receivers not long after 1996.

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If Sanders had to deal with the 21st-century news cycle in his best seasons, his narrative would be: A) buzzy player on a bad defense for the Falcons; then B) superstar for 49ers and 1996 Cowboys, like Sherman in 2012-13 and Revis from 2009-11; then C) a long wind-down full of accusations of being overrated as the Cowboys slowly deteriorated.

But Sanders almost certainly earned each and every one of those Pro Bowl appearances. He was still a useful nickel defender when he came out of retirement at age 37. Evaluating pass defense is complicated: Not only must you comb through the game film and play-by-play for passes that were never thrown, but you have to account for the quality of the opponent, the pass rush, the scheme and the other defenders.

Sherman and Peterson have each faced Peyton Manning and Philip Rivers already. The Cardinals blitz wildly, while the Seahawks play vanilla and the Patriots groove to head coach Bill Belichick's unpredictable beats. Cromartie makes Peterson easy to challenge, while Maxwell makes Sherman easy to avoid.

Going back 20 years, Sanders went from a bad organization that constantly faced the Jerry Rice 49ers to a pair of outstanding teams, the second of which crumbled around him, taking much of the analytic evidence of his greatness along for the ride.

If Deion Sanders looks ordinary under close examination, Revis, Sherman or Peterson don't stand a chance.

None of these cornerbacks is ordinary. It's our expectations that are out of whack. Great cornerbacks do not have to earn shutdown status any more than a great quarterback needs to be dubbed elite by a jury of my peers. They do not have to be perfect. They simply must make good defenses great and lead them to Super Bowls.

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Prime Time and Sherman have already done that. Revis and Peterson have the potential to do it. Other cornerbacks like Haden, Davis and Aqib Talib can still join the conversation.

It's not about labels, perfection or magic—it's about reality. Sherman, Revis and Peterson are really, really good. If we shut down all the nonsense about shutdown cornerbacks, we can appreciate just how much they are capable of.

Mike Tanier covers the NFL for Bleacher Report.