Everyone expected New England to dominate on offense this season, but the performance of its defense has been a pleasant surprise. A remade secondary is beating expectations and is ready for its hardest task so far

Everyone saw the Patriots offense coming. But the defense? The Pats are allowing 19 points an outing through the first quarter of their season.

Without a stingy defense last season, the Patriots wouldn’t have hoisted their fourth Lombardi Trophy. Last year’s unit was built around a man-to-man scheme that featured All-Universe cornerback in Darrelle Revis, press-coverage artist Brandon Browner and the inconsistent-but-above-average Kyle Arrington at nickelback. When all three disappeared this offseason, it was widely presumed that New England’s ability to play foundational man coverage would also vanish—especially after the Patriots filled the three corner spots with undrafted second-year man Malcolm Butler and veteran castoffs Tarell Brown and Bradley Fletcher. A repeat of last year’s scheme would be impossible; you can’t hide mediocrity in man coverage.

No longer able to out-execute offenses, it was thought that the wizardly Bill Belichick would concoct a complex, amorphous scheme to outsmart them. But Belichick really hasn’t gone all-in on weekly defensive overhauls since the early 2000s, when he had an uncommon group of savvy veterans such as Willie McGinest, Mike Vrabel, Tedy Bruschi, Roman Phifer, Lawyer Milloy/Rodney Harrison and Ty Law.

In the 2010s, Belichick’s defenses have still been versatile, but the overall M.O. has been a vanilla, fundamental-based defense when opponents are near the middle of the field and a schematic wrinkle or two waiting for them when they reach field-goal range. It’s classic bend-but-don’t-break.

Remarkably, New England’s less talented 2015 defense has continued to employ (and thrive with) the same man-heavy bend-but-don’t-break approach. The only consistent variation is they’ve played some Cover 3 on first and second downs, when corners often match-up outside and a single-high safety oversees four underneath defenders. This is the most basic, most common coverage in the NFL. In other situations, particularly passing ones, the Patriots have often employed their standby variations of man-to-man. An unofficial rule for defense: the more talented you are, the more basic your scheme can be. A team with New England’s cornerbacking group should not be prospering with Cover 3 and pure man-to-man.

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So what’s gone into it? For starters, the club saw something in Malcolm Butler that others did not. Yes, Butler was the hero of Super Bowl 49. But one play doesn’t trump the fact that he went undrafted. More than any other defensive position, playing cornerback is about raw talent; that’s why it has the highest percentage of starters who are former first-round picks. It’s unheard of for an undrafted man to go from being the No. 5 or 6 corner as a rookie to being used as a No. 1 in his second season. And make no mistake, the Patriots are using Butler as a No. 1. That plan was apparent immediately in Week 1 when Butler shadowed arguably the league’s best receiver, Antonio Brown.

Butler has played well. So has Tarell Brown, a 30-year-old who understands the nuances of his position. Bradley Fletcher, on the other hand, has not. In fact, Fletcher was released after giving up the same type of deep balls in perimeter solo coverage that became his bugaboo in Philadelphia. Filling his void has been Logan Ryan, a third-year pro who has pinballed all over the cornerbacking depth chart, as well as undrafted rookie Justin Coleman, who at the tender age of 22 is already on his third team after being let go by Minnesota and Seattle.

“I’m not really surprised [at our success],” safety Devin McCourty says. “We knew for us to be a good team we were going to have to play the concepts we’ve been playing [in recent years] and we felt like we had the personnel to do it.”

Still, considering the talent drop-off at cornerback, it’s been an overachieving group in 2015.

Is the success just a misleading case of the Patriots having faced soft offenses? Pittsburgh, without Le’Veon Bell, posted 21 points against them in the opener and averaged seven yards a play. In Week 2, the Patriots faced Bills quarterback Tyrod Taylor in only his second NFL start. In Week 3, it was the Jaguars, who are much better offensively than people realize, but still not equipped to counter a Patriots offense that scored on all nine of its possessions (discounting kneel downs). And in Week 4, the Pats saw a Cowboys team that didn’t have its star quarterback and wide receiver, and had just lost top receiving back Lance Dunbar to a torn ACL and MCL. (Anyone who has watched Sergeant Checkdown Brandon Weeden this year knows that losing Dunbar is a big deal.)

If ever there were a week for the curtain to be pulled back on the Patriots, this is it. They’re facing a Colts team Sunday night that will have Andrew Luck. True, the Colts didn’t play well with Luck in September, but a two-game sample doesn’t outweigh the fact that Indy boasts more raw wide receiving speed (T.Y. Hilton, Donte Moncrief and Phillip Dorsett) than any other team in the league.

Typically, defenses that get by with mediocre cornerbacks camouflage that with a dynamic pass rush. But the Patriots are nothing special here either. Sinewy, agile end Chandler Jones is an excellent five-tool player, but his “speed rushing” tool is only good, not great. Every other regular contributor up front is a better run-down player than pass rusher. New England has averaged four sacks a game this year (third best in the league), but Tyrod Taylor’s pocket struggles in Week 2, which were masked by some hefty passing stats late in the contest, inflated those sack numbers. Take out that game and the Patriots fall in the middle of the pack.

Ho-hum corners and modest pass rushers, and yet we’re talking about the seventh-ranked scoring defense in the league? The only remaining explanation must be excellence up the middle of the D.

The Patriots have one of the best interior back-ends in football. Start with safety Devin McCourty, the one free agent DB the club did retain. He offers range and awareness as a centerfielder, but more importantly, he’s a former corner who has the versatility to drop down and cover tight ends or, occasionally, slot receivers. (He was tremendous against Jason Witten last Sunday.) McCourty is also a deft free defender at the mid-level range, which is critical in some of New England’s man-to-man coverage rotations.

“That’s the toughest thing,” McCourty says. “You’ll watch our film and some of it looks the same, but a guy could be in a similar position and be doing something totally different depending on who we’re playing and what we think their strengths are. The biggest thing for me is when I’m deep, everything’s all about not giving up the big play, not being out of position so I can help guys out on vertical routes. Whereas when I’m closer it’s about trying to anticipate and seeing different things and what’s going on in the defense, and what the offense is trying to do right away.”

McCourty’s malleability opens more repetitions for the other three safeties New England plays, all of whom were drafted in the second round, save for Duron Harmon, a third-rounder in 2013. The first is Patrick Chung, a thumper who last season suddenly learned to play man-to-man in the box. He’s very physical here. Then there’s second-round rookie Jordan Richards, whose fluid movement stands out on film, particularly when he’s in the box. The Patriots may not have a voluminous scheme, but with depth and versatility at safety, they’re able to sprinkle unique spices into what are otherwise plain coverages.

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“Different personnel packages allow guys to have different roles,” McCourty says. “When you can have guys that are all focused and zoned in, play different roles plays to everybody’s strengths.”

Up front, the middle of this D is stouter. Jamie Collins, a former part-time college safety and another former second-round pick, is the most athletic inside linebacker in the league. He can handle most man coverage assignments and has a supple burst in traffic that makes him a fearsome blitzer. Fellow inside ’backer Dont’a Hightower has become a deft blitzer as well, relying more on physicality and timing. It’s no accident that many of the Patriots’ man coverages now feature five-man blitzes with one of these guys rushing inside. The Patriots have also employed more of the trendy double A-gap blitz looks, with both ’backers aligned directly over the center, where they can either rush, set up stunts for defensive linemen or drop into coverage after the offense has adjusted its protection. The beauty is that Collins and Hightower’s blitzes also work against most running-game concepts. The Patriots can rush one of these guys on early downs and not be caught off-guard by play-action. Plus, presumably the Patriots are practicing these concepts more diligently because they’re staples that are deployed on so many different levels.

Having answered how the Patriots are prospering on defense, all that’s left is to answer whether that prosperity can continue. The more film teams see of a so-so player, the more vulnerabilities they’ll discover. Once those vulnerabilities are exploited, the whole league smells blood. If that’s going to happen to New England’s corners, it will start this Sunday night. However it shakes out, the contest against the Colts will reveal a lot about the Patriots’ defense.

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