Peterson's responsibility tops Sherman's

Easy is a relative term.

To some, math is easy. To others, it’s hard. Examples can be found in every walk of life, on every corner of the globe.

But when easy is discussed by people at the top of their profession, such as Arizona Cardinals cornerback Patrick Peterson, it’s time to pause and listen.

“Obviously, his job is definitely much easier than mine,” Peterson said on a sports radio show in Arizona last week, referring to Seattle Seahawks cornerback Richard Sherman. “If you look at their scheme and look at our scheme, he’s a cover 3 corner. Period.”

Then the jousting match began.

Sherman said Peterson wasn’t a “lockdown corner.” Peterson responded by saying Sherman gets help over the top of the secondary. Then Sherman came back again, tweeting Peterson that he gives up “career days” and the Cardinals “ask u to stop them. Not let them score at will.”

First, the disclaimer: Sherman is great. There is no denying it. He has become one of the league’s top cornerbacks because of his athleticism and ability.

Second, the facts: Sherman spends the majority of his time covering the left side of the field.

Why is this so important? It, in essence, is the downfall of Sherman’s claim.

“If you’re an offense, you can just put your second receiver on that side of the field and you know he’s going to get Sherman,” ESPN NFL Insider Matt Williamson said. “You can dictate who Sherman’s going to cover.

“That in itself makes his job much easier.”

According to ESPN Stats & Information, Sherman lined up at left cornerback in 15 games last season, excluding the postseason. He appeared on the right side, just covering the slot, in one game. Sherman was challenged only twice when he lined up on right side, according to ESPN Stats & Information.

By comparison, Peterson lined up at left cornerback in 10 games and right cornerback in 10 games.

Looking at the numbers, Sherman appears to be the better cornerback. He was ranked as the sixth-best corner by Pro Football Focus last season while Peterson was 16th. In coverage last season, PFF ranked Sherman No. 1 and Peterson fifth.

Peterson was in coverage for 690 snaps, compared to Sherman’s 549, according to PFF. Peterson was targeted 90 times compared to 58 times for Sherman, who gave up 30 receptions to Peterson’s 49. Sherman’s completion percentage was 51.7. Peterson’s was 54.4 percent, with 32 more targets. Sherman gave up 267 fewer yards than Peterson and 172 fewer yards after the catch.

But what can’t be lost is that Sherman is generally facing inferior talent than Peterson.

As Williamson pointed out, by Sherman being anchored to the left side, it makes it easier for teams to plan around him. According to PFF, Sherman covered a team’s top receiver 31 percent of the time, Peterson 55 percent of time.

To bolster Williamson’s statement, PFF’s numbers indicate Sherman covered the No. 2 receiver 31 percent of the time, almost twice as often as Peterson. Sherman is seeing inferior talent more often than Peterson and taking advantage of it, securing eight interceptions last season to Peterson’s three.

“I think to play man against [the top wide receiver] on the other team is the most responsibility you can put on any corner,” Williamson said. “That’s the Deion [Sanders], [Darrelle] Revis treatment.

“That’s Peterson Island.

“It’s not like he’s going to eliminate that guy, but if they split 50/50 against a Pro Bowl wideout, your 10 should be able to eliminate the other 10. If their best weapon has a down game by his standards and it’s a draw against Peterson one-on-one, you should win because then you can double their second receiver, you can blitz more. It gives you so many other options.”

It also helped Sherman that he had two Pro Bowl safeties who had his back, Earl Thomas and Kam Chancellor.

One of the basic tenants of Seattle’s Cover 3 defense is that the field is split into thirds, so Sherman has one-third, Thomas has one-third and the right cornerback has one-third. Each defensive back is responsible for their third and tries to avoid letting a receiver get behind them.

In Arizona, which plays a Cover 1 scheme, it’s basically every man for himself. There’s typically one safety deep as the last line of defense. Peterson takes the top receiver, and assignments cascade from there with the second corner taking the second receiver, strong safety on the tight end and linebackers typically on running backs.

But this is the advantage Sherman has. With Thomas, who is arguably the league’s best free safety, roaming the deep secondary, Sherman can take more risks, which leads to more interceptions.

“If it’s questionable -- should I jump this route or not? -- I think if I’m the coach of the Seahawks, I would advise Sherman to do it at a higher percentage of the time than Peterson because if he doesn’t get there, Thomas will probably make up for it,” Williamson said.

Peterson played with strong safety Adrian Wilson during his first two seasons, but Wilson wasn’t the same hard-hitting bruiser he developed into throughout his career. But in 2011, he still made the Pro Bowl. Last season, Peterson played with a rotation of safeties. Tyrann Mathieu, Rashad Johnson and Tony Jefferson shared time at free safety while Yeremiah Bell -- who, like Wilson, was toward the end of his tenure with Arizona -- wasn’t as fast or as quick as his younger days.

Being aggressive, knowing there’s help behind you, doesn’t always result in a pick.

Last season, Sherman was flagged for 10 penalties, five of which were for defensive pass interference and totaled 98 yards. Peterson had six flags, of which two were defensive pass interference for 28 yards.

“In terms of judging every corner around the league, I’d still put Peterson on the aggressive side,” Williamson said. “I don’t think he’s a cautious player by any stretch of the imagination.

“Sherman is as good as anyone at jumping routes and is as aggressive as anybody, and a lot of it has to do with scheme and having Thomas back there.”

Both Peterson and Sherman are considered great cornerbacks in their own right and scheme, but whose job is easier? The question may never have a clear answer, but Peterson has been shouldering more responsibility than his rival to the north.