The Chiefs and Titans have been the NFL's biggest surprises through four weeks, and a commonality has set up both teams for continued success

Defense has been the key for the surprising starts in Kansas City and Tennessee this season, and no players have performed better than defensive tackle Dontari Poe (left) and linebacker Zach Brown. (Getty Images)

No one foresaw the Kansas City Chiefs and Tennessee Titans entering October with a combined record of 7-1. There is a common thread hallmarking these early success stories, who also happen to square off Sunday in Nashville. It's defensive play that is both vigorous and well-styled for today’s NFL.

Each defense is under new leadership. Andy Reid, shortly after being hired by Kansas City, wisely chose to keep the defense’s 3-4 foundation intact, tapping longtime New York Jets assistant Bob Sutton as his coordinator. In Tennessee, defensive coordinator Jerry Gray was retained despite the Titans allowing the most points in football last season. But some of Gray’s duties were shifted when the team hired former Saints coordinator Gregg Williams, fresh off his Bountygate suspension, as a senior defensive assistant.

Sutton and Williams inherited two of the league’s more vanilla defenses and have seasoned them for a flavor that even Emeril Lagasse would envy. Let’s examine four key ingredients.

1. Solid bases

Great defense in today’s NFL is about forcing turnovers and winning on third down. (The Chiefs rank first in the AFC in both categories; the Titans rank third and second, respectively.) You can’t do either of those if your base defenese fails to hold serve on first and second down. The Chiefs’ base 3-4 and the Titans’ base 4-3 have been stingy enough to create third-and-long situations; that's where these creative coordinators thrive.

The credit starts up front. For Kansas City, athletic second-year force Dontari Poe has been the NFL’s best nose tackle through four weeks. His lateral agility, amplified by his raw strength, has allowed the Chiefs to play true two-gap football up front. This has enabled underrated ends Tyson Jackson and Mike DeVito to be more proactive in their gap assignments, and it has kept swift, agile linebackers Derrick Johnson and Akeem Jordan free to run and chase.

The Titans have an equally athletic pair of linebackers in Akeem Ayers and bourgeoning 2012 second-round pick Zach Brown, a track star from North Carolina. Playing in a true 4-3, the Titans’ defensive line aims to penetrate gaps rather than clog them. The superb play here of third-year defensive tackle Jurrell Casey has made life easy on the rest of the rotating D-linemen.

Worth noting is that both defenses also have a formidable run-stopping safety: Eric Berry (Chiefs) and Bernard Pollard (Titans). Both are fast enough to make plays coming from the third level, physical enough to play in traffic, savvy enough to identify potential running lanes and athletic enough to operate in space, whether it's short-area pass defense (Berry's specialty) or downfield tackling (Pollard’s forte).

2. Man stoppers on the back end

Ten years ago, a sturdy run-stopping front seven was all a defense needed in order to create third-and-long. Nowadays, with so many dynamic tight ends, versatile running backs and smart-audibling quarterbacks, winning on first and second down requires stopping the pass. The athleticism at linebacker and strong safety enable the Chiefs and Titans to do this. But more than that, there are the adept cornerbacks.

Quality man-to-man corners are mandatory. For one, defensive coaches know that nothing disrupts the timing of route combinations like a corner’s stout jam at the line of scrimmage and stride-for-stride joyride in a receiver’s hip pocket. For two, with more offenses playing up-tempo, a defense almost has to play man because there’s not enough time before the snap to communicate zone responsibilities. (It’s much easier for defenders to just say, “I’ve got him!”)

Titans cornerback Alterraun Verner is tied for the league lead with four interceptions, including one he ran back for a touchdown against the Texans. (John Rivera/Icon SMI)

Under former coach Romeo Crennel, the Chiefs played a lot of man coverage, which is why they signed Brandon Flowers to a six-year, $49 million contract in 2011. Wanting to maintain this approach, Reid and Sutton this past spring signed the most expensive free agent corner on the market, Sean Smith (three years, $18 million). The lanky ex-Dolphin has been outstanding, matching up primarily on the outside against No. 2 receivers. The unheralded Flowers, who has long been one of the league’s finest boundary man-defenders, has drawn the No. 1 assignments, often without safety help. He played Dez Bryant very tough in Week 2 but fell victim to some of Bryant’s insane circus catches. Five days later, fighting a bum knee, Flowers held DeSean Jackson to three catches for 42 yards on seven targets. (Flowers’ status for Week 5 is in question; he’s dealing with knee inflammation.)

For Tennessee, Jason McCourty and Alterraun Verner spent the past few years predominantly playing conservative off-coverage concepts in zone-heavy game plans. Naturally, they were presumed to be so-so corners. But with Williams now mixing a lot of man coverages in with the zones, McCourty and Verner have, by necessity, become more assertive. The results have been spectacular. Verner has a league-leading four interceptions, mostly great individual plays. McCourty has barely seen the quarterback glance his way.

3. Sub-package coverage

Just having good No. 1 and 2 corners is not enough anymore. The influx of three-receiver sets, dynamic tight ends and versatile running backs demands that a defense have at least four, and preferably five, abled man-to-man defenders. An athletic linebacker can suffice, even in nickel and dime situations (Kansas City's Derrick Johnson and Tennessee's Zach Brown are both very fluid here). And a starting safety who can play solo man against tight ends brings a significant boost. Berry, after struggling mightily in man coverage at times last season, has emerged in 2013 as one of the best cover safeties in football. For Tennessee, Pollard is less reliable, though he has done better in recent weeks.

Then, of course, there’s the increasingly significant nickel back position. More spread offensive sets means more defensive backs getting major playing time. The more those defensive backs play, the more multidimensional they have to be. Offenses that spread out 30 times a game aren’t using the passing designs 30 times over. There are occasions where nickel backs, particularly those who specialize in playing the slot (like Tennessee’s Coty Sensabaugh), must be force run defenders.

In fact, because offenses are expanding their run concepts out of spread sets, we’re seeing more defenses use surer-tackling safeties in sub-packages. Essentially, the No. 3 safety is replacing the No. 2 linebacker. Or, he’s replacing the No. 4 cornerback, which is how the Titans use veteran George Wilson. There are also occasions where Wilson replaces a linebacker in the base D to form a “big nickel” package.

The Chiefs have a hard-hitting nickel corner in Dunta Robinson and behind him an intriguing first-year corner in Marcus Cooper. But in dime situations, it’s not Cooper getting the nod, but rather, Quintin Demps or Husain Abdullah. Thanks to various cornerback injuries, both of these backup safeties have actually seen time in nickel, too, where they are serviceable in man coverage. Which brings us back to the main point: the more quality man-defenders a defense has, the better. Tennessee and Kanas City have plenty.

4. The blitzes

Having trustworthy man defenders emboldens Sutton and Williams to dial up more blitzes. And because Sutton and Williams can put so many athletic linebackers and extra defensive backs on the field, they have a lot of speed to work with in their pressure designs. This expands the blitzing capabilities—and, inherently, the blitz disguises—as deeper second-level defenders and corners are threats to rush the passer.

We’ve especially seen this in Kansas City.

A defensive coordinator does not always have to call blitzes in order to be aggressive. Instead, he can instruct his players to have an attack mindset in man coverage concepts. This creates pressure opportunities because anytime the offense keeps a tight end or running back in to help with pass protection, they’re inviting a blitz from whichever defender has that player in coverage. This is known as a “green dog blitz.” It’s a staple of Gregg Williams’ system and common throughout the league.

One reason Gregg Williams’ defenses are always good at green dog blitzing is his aggressive presnap looks compel the offense to make cautious adjustments in protection. In the example above, Foster did not have to stay in and block—there were five offensive linemen to combat four pass-rushers. But prior to the snap, the Texans could not possibly know—or assume—that the Titans would only send four of seven possible rushers. Even if they did know that, they couldn’t know who the four rushers would be.

In response to this look, Houston’s zone-blocking line slid left, away from Foster’s help protection on the right. This made Foster solely responsible for 280-pound defensive end Derrick Morgan. Right tackle Derek Newton was unable to double back and help Foster because he had to pick up Brown’s green dog blitz. Morgan easily dismantled the overmatched Foster, forcing Matt Schaub to step into a Kameron Wimbley sack. These are the types of opportunities Gregg Williams’ tactics create.

With Tennessee’s and Kansas City’s offenses having conservative passing games that are essentially aimed at hiding their quarterbacks, you can bet these defenses will be in full attack mode Sunday.

Continue to Page 2 for my Thursday night preview.

THURSDAY NIGHT PREVIEW

Young quarterbacks EJ Manuel (left) and Brian Hoyer step into the primetime spotlight when the 2-2 Bills and 2-2 Browns square off Thursday night. (Getty Images)

Browns offense vs. Bills defense

After getting torched deep by the New York Jets in Week 3, Buffalo’s secondary—which has been without top three corners Stephon Gilmore, Leodis McKelvin and Ron Brooks, as well as franchise safety Jairus Byrd—rebounded with stifling man coverage against Baltimore’s downfield play-action game in Week 4. Safety Aaron Williams, starting at his former cornerback spot, had one of the best individual performances of any player this season.

Williams and his colleagues can expect to be attacked deep for a third straight game Thursday night. Since Josh Gordon’s return from suspension, the Browns have been more comfortable with the vertically stretched passing designs in Norv Turner’s system. Brian Hoyer has been very stellar staying in the pocket and efficiently working through progressions. He has benefited from tremendous pass-blocking, particularly by left tackle Joe Thomas, who has been almost flawless playing on an island.

Despite what Mario Williams’ sack numbers suggest, the Bills don’t have a prominent pass-rusher to challenge Thomas. They do, however, have an excellent interior blitzing threat in supple rookie middle linebacker Kiko Alonso, and they have a schemer in coordinator Mike Pettine who does great work with hybrid fronts and disguises. The Browns' rushing attack last week looked the best it has all season, so Cleveland would be wise to stay true to the run and make this Bills front seven prove that its stellar gap discipline against the Ravens was not an aberration.

Bills offense vs. Browns defense

Speaking of running the ball, that’s what the Bills did last Sunday. Fifty-five times. Fullback Frank Summers played 42 of the offense’s 84 snaps, performing admirably as a classic black-and-blue lead-blocker. It was a great strategic adjustment by Doug Marrone, who likely realized after losing to the Jets that EJ Manuel isn’t ready to have so much on his plate just yet. By going back to basics —like two-back or two-tight end personnel and a between-the-tackles rushing attack—Marrone was able to create a defined, one-read passing game for his rookie quarterback, leaning heavily on play-action.

Interestingly, most of those one-man reads were directed for rookie wideout Robert Woods, not sixth-year star Stevie Johnson. Don’t be surprised if Woods fully supplants Johnson atop the pecking order. He has better speed and quickness than Johnson and is virtually the same size (6-1 or 6-2, 200 or so pounds). We’ll know which receiver Cleveland believes is Buffalo’s No. 1 by who Joe Haden defends. The fourth-year pro has been a shutdown corner through four games.

Against A.J. Green and the Bengals last week, the Browns predominantly used matchup zone concepts out of two-deep coverages. Safeties T.J. Ward and Tashaun Gipson gave outstanding help downfield. This week, the Browns likely will play more man-to-man, with one of the safeties dropping into the box. They’ll want to make the Bills reluctant to run.