The NFL is a constant game of "Can you top this?" for coaches and play-designers.

There is a zone blitz for every West Coast offense and a 46 defense for every run-and-shoot. Even when schemes fade due to their limitations, elements stick in the modern game.

The NFL of 2017 is the most schematically, formationally diverse we've ever seen, and that will continue in future seasons. Coaches will tell you that it's a league of matchups—and about getting the personnel and numbers together in ways that stop an offense or fool a defense. That's led to new roles for players at every skill position on both sides of the ball.

Fullbacks had better be able to motion from the backfield out wide to present a linebacker with a matchup issue if they want to stay on the field. Cornerbacks need to cover outside and in the slot, where the responsibilities can be completely different. Linebackers who can't cover won't be in the game plan often. And on and on.

The NFL1000 team of scouts has been watching tape all season, and we've noticed trends that are changing the game. Some are adapted from the NCAA, while others are revisions of pro concepts revved up for today's NFL.

Our team:

Lead scout: Doug Farrar
Quarterbacks: Mark Schofield
Running backs/fullbacks: Mark Bullock
Receivers/tight ends: Marcus Mosher
Offensive line: Ethan Young
Defensive line: Justis Mosqueda
Linebackers: Derrik Klassen
Secondary: Ian Wharton

Here are 10 schematic concepts that are finding more favor in the NFL, and how they might progress.

Run-Pass Option

We're seeing the run-pass option for two reasons: They expand a central tenet of offensive football while reducing risks, and quarterbacks are entering the league with experience in these designs.

At the core of designing a play, offenses try to identify a defender and force him to choose between two options. Your old-school option leaves a defender unblocked and stuck in conflict between the quarterback and the pitch man. If the defender collapses on the pitch, the QB keeps the ball. If the defender attacks the signal-caller, the QB flips the ball to the pitch man.

We can see this in the passing game as well. On Sunday, the 49ers scored on the Mills, or Pin, concept. That uses a post route and a dig route to put the free safety into conflict, and then the QB reacts to what the safety does. If he plays the post, the quarterback throws to the dig. If the safety rolls up on the dig, he throws the post.

Put a defender into conflict, gauge his response and react accordingly.

So when Cam Newton takes a snap, puts the football in Christian McCaffrey's belly and reads Kiko Alonso's response, he's making a progression read. If Alonso crashes down on the run, he throws the skinny post to Devin Funchess. If Alonso drops under the post route, Newton hands the ball to his rookie running back.

This simplifies the read structure for the quarterback while reducing the risk associated with running the play. Instead of throwing either a post route or a dig, where one of the routes could result in an interception, now you have one potential pass and one potential run.

Because RPOs contain that core tenet of a conflicted defender, that is one reason more and more teams are running these designs. It's not just the quarterbacks you would expect, such as Newton, Marcus Mariota or Deshaun Watson before he suffered his injury. But guys such as Aaron Rodgers, Blake Bortles and Kirk Cousins are using RPOs as part of their game plans each week.

As more and more quarterbacks enter the NFL with a skill set rooted in running RPOs, coaches are faced with the prospect of hoping/waiting for developmental leaps or incorporating plays from their past into the playbook. From what Andy Reid has done the past few years with Alex Smith to how Bill O'Brien helped Watson this year, using these familiar concepts helps QBs succeed.

The RPO is here to stay.

—NFL1000 QB Scout Mark Schofield

Chiefs' Multiple-Option Passing Game

It's not like Andy Reid just woke up one day and decided to work spread-offense concepts into his offense.

When he became the Chiefs' head coach in 2013, he hired former Vikings head coach Brad Childress, who had once been his offensive coordinator in Philadelphia, as his special projects coach and "spread game analyst." He also hired Chris Ault, the former Nevada coach who brought the Pistol formation to prominence with Colin Kaepernick as his quarterback, as a consultant from 2013 through 2015.

Reid had been cooking these ideas up for a while, and they made appearances in Kansas City's offense. But it's in the 2017 season that we've seen them come to fruition. Now, Reid and the Chiefs have the most multiple and potentially dangerous offense in the NFL, because they combine West Coast passing concepts with option runs and passes and a fully diverse running game.

Most of this improvement is about personnel. In receiver Tyreek Hill, they have a speed-burner who can run fake jet sweeps to alter defensive looks pre- and post-snap. And Kareem Hunt fits the system perfectly as the running back adept enough with route concepts to be a productive player in all kinds of play-action and pass-option looks.

The power-shovel read is a primary concept in Kansas City's offense. Quarterback Alex Smith, who played in an option offense for Urban Meyer at Utah, reads the defensive end as the ball is snapped. A shovel pass is an option if there's a blitz or an easy pass rush; a handoff works if not.

In their Week 2 27-20 win over the Eagles, Smith dumped a shovel pass off this look to tight end Travis Kelce for a 15-yard touchdown. The kicker on this play was sending Hill in motion from right to left pre-snap and having Hill work his way back to his original right slot position after the snap. This sent Philly's linebackers out of position, and Kelce had an easy go to the end zone.

When the idea is to give the ball to Hunt off a read, the Chiefs will use their receivers as blockers in addition to any sweeps and slides. Reid and Smith have perfected the idea of predicating their own offensive action off the actions of either the front-side or back-side defensive end, so if Smith wants to get Hunt outside on an option toss, that's available to either side.

It helps that Hunt is a great receiver and pass blocker. There's no incentive to take him off the field, and that's one reason he ranks second in the NFL in rushing yards with 800 behind only Pittsburgh's Le'Veon Bell. Not bad for a third-round rookie.

The reason Kansas City's option plays work so well when other similar concepts have been snuffed out by NFL defenses is the addition of a complete, efficient passing game. Smith is obviously the point man here, and the benefit for him is that the increase in defensive confusion has allowed him to throw for many more big plays downfield than he has in past seasons.

Smith has always been thought of as a "game manager," but in this offense, the concepts give him easy openings to let the ball fly.

When the Chiefs move Hill in a fake sweep motion in the passing game, it's not about giving him the ball on an option principle; it's about his movement helping Smith to identify whether the defense is man- or zone-based, and where the mismatches will be.

At that point, he can simply go through his progressions and make the right choice as any experienced NFL quarterback would, with the help of formational diversity and the addition of cumulative confusion on the part of the defense.

That's why the Chiefs offense works so well and why you're seeing other teams like the Eagles adopt similar structures in recent weeks. The combination of pre-snap motion, post-snap option and a fully developed passing game is just about impossible to beat.

— NFL1000 Lead Scout Doug Farrar

One-Read Throw

In a 2016 coaching clinic presentation, Sonny Dykes, then the head coach at the University of California, stated this: "Football is a simple game. If we can find your weakness, we will beat you with it. When you play teams with heavy man-coverage schemes, it is all about the matchup you can create."

We have outlined some of the ways teams are trying to create those matchups on offense, from RPOs to multiple-option passing attacks. Another is the one-read designed throw in the passing game. If you were watching the Lions-Packers game a few weeks ago, you heard Jon Gruden outline how more teams are incorporating this into their passing games.

The design is simple, and it builds on a basic premise: Get the ball to your playmakers in space and with blockers in front. The play that sparked Gruden's discussion came out of a three-receiver trips formation, with Jordy Nelson lined up as the inside receiver and Davante Adams and Randall Cobb outside of him. Nelson ran a quick out pattern, while both Cobb and Adams immediately looked to block for him.

Green Bay is not the only offense running these designs. Watch the Steelers; they sometimes look to get the football into Antonio Brown's hands in a similar manner. Not only do they do it with Brown releasing to the flat, but they can also do it on crossing patterns from Brown, with receivers on both sides of the formation releasing to block downfield.

The beauty of these designs is they get playmakers the football in space with blockers, and they can also be effective against both man and zone coverage schemes. Plus, they operate as an extension of the running game, with the quarterback getting the ball out quickly to negate any pass rush up front, and the ball-carrier usually has just one defender to beat after the reception.

Screen passes have been a staple of offensive football for decades, and the one-read throw builds upon that concept and moves the starting point past the line of scrimmage. Giving the receiver some blockers, getting the football in his hands quickly and giving him space to operate is the next step in the growth of the screen passing game.

— NFL1000 QB Scout Mark Schofield

Jet Sweep Motion

One of the biggest trends is the use of the jet sweep.

It asks a receiver—usually a smaller, quicker guy from the slot—to motion across the formation from one side to the other. It's like an end-around or reverse, but instead of the receiver motioning behind the running back in the backfield, he runs parallel to the line of scrimmage. The ball is snapped before the receiver reaches the quarterback, and the receiver is given the ball in stride to try to outrun defenders to the edge.

The jet sweep itself isn't new; it's been around for a while and has been used more frequently to get the ball in the hands of speedy receivers. However, a development we have seen over the last few years is faking the jet sweep.

Teams such as the Chiefs with Tyreek Hill and the Rams with Tavon Austin fake the jet sweep multiple times each game before handing the ball off to their running back on one of their base runs plays in the opposite direction.

What this motion, sometimes referred to as "ghost motion," does to a defense has been greatly beneficial to offenses that use it regularly. The linebackers on the second level and the back-side defensive end are often frozen for an extra second as they read the jet-sweep fake to make sure the receiver doesn't get the ball. That allows the offensive line extra time to secure the defensive linemen and work up to their spots to reach the second-level defenders.

The results speak for themselves.

It's no coincidence the two teams that fake the jet sweep most often, the Chiefs and Rams, both have a top-five rusher. Kareem Hunt's fantastic start to life in the NFL has been aided by this schematic wrinkle, while it has also contributed to Todd Gurley's resurgence this year.

Other teams are starting to catch on. Almost every team with a speedy slot receiver has tried it in an effort to further their running game. The Saints have used Ted Ginn Jr. and Brandin Cooks to fake the jet sweep; the Redskins have deployed Jamison Crowder in similar fashion over the past few weeks; as have the Lions with Golden Tate.

It's quickly replacing the fake end-around, or orbit motion, which sends the receiver behind the running back, giving the linebackers more time to react and chase down the receiver should he get the ball. The jet sweep happens quicker and thus is more of a threat to the linebackers at the second level.

While the rest of the league begins to catch up and install the jet sweep and the jet-sweep motion, the Rams and Chiefs have already started to incorporate the next progression into their offense.

As defenses catch on and begin to adjust, Sean McVay and Andy Reid have begun to run play-action passes and screens off the jet-sweep fake. Instead of handing the ball off, we've seen the quarterbacks execute a play-action fake while the jet-sweep receiver turns his motion into a wheel route and bursts down the sideline. The Rams even had Gurley fake his run and burst up the seam on one jet-sweep fake earlier this year.

Similarly, the sweep can be turned into a quick screen. As defenses begin to ignore the jet-sweep fake and overpursue the front side of the run, offenses can leak out a tight end and/or a tackle from the back side to block on a screen pass. There have also been times where they use the jet-sweep motion to draw a defense to the back side, only to throw a screen to the running back on the opposite side.

It's taking backfield action to the next level of deception, and offenses around the league are benefiting. The offense only needs to hand it off on a jet sweep once or twice for the opposing defense to have to respect the threat.

It causes a separation between the first tier of the defense (defensive line) and the second tier (linebackers), which the NFL hasn't figured out how to fully counter yet. Until the league does, expect it to become more and more popular as a backfield distraction that is a pain for linebackers to deal with.

— NFL1000 RB Scout Mark Bullock

Dual Pre-Snap Motion

While pre-snap movement is not a new concept, a new twist we're seeing is multi-motion.

In college, play-callers such as Matt Canada and Jonathan Smith run chaotic group shifts and trio motions. We haven't seen that in the NFL yet, but we are seeing subtle dual pre-snap motion combinations. The results have been impressive.

What do dual motion concepts do so well? Two things: 1. Expose opponent coverage, and 2. Allow skill-position players to exploit any matchup conflicts that change from initial coverage detection.

A popular combo being used this year is flex/jet sweep; Mark Bullock wrote about the problems jet sweeps can cause defenses above.

When prefaced with an H-Back flexed tight or "Joker" flexed into the slot, it can help identify if the defense is in man (depending on who follows the flex player). It can also show if the resulting jet sweep is going to be a one-read footrace for the jet man or if he needs to wait for the route to develop with the intention of flooding the targeted zone.

It also jumbles up one of the best ways defenses counter jet sweep, backside RNR rotation. By reordering and stretching the backend rotation right before the snap, and then immediately yanking on that with jet sweep, defenses don't have time to adjust.

The Jets offense utilizes these concepts often under new coordinator John Morton, and the chaos they create pre-snap has been effective in getting secondaries to play back on their heels. This has allowed Morton and Co. to attack opposing secondaries with their longer developing route combinations without having to worry about their protection woes as much.

The Jets are a great example of just how useful these concepts can be and how much they can do for an offense.

— NFL1000 OL Scout Ethan Young

Double-Slot Receiver Concept

According to Football Outsiders' charting data, teams lined up in "11" personnel (one back, one tight end, three receivers) on 60.4 percent of their plays in 2016, an all-time high. Defenses responded by using five or more defensive backs (usually three cornerbacks, with some "big nickel" three-safety exceptions) more often.

This has been an upsurging trend over the last half-decade. Offenses look to spread the field by taking the fullback out of the picture, and defenses move to check those trends by removing the third of fourth linebacker from the formation, depending on whether the base scheme is 4-3 or 3-4.

As the three-receiver set has become the norm, the position of slot receiver (and, by proxy, slot defender) has grown exponentially in importance. And as defenses have responded with more advanced coverages across the field, the addition of a fourth receiver provides a new wrinkle.

Teams will run many different concepts with four receivers, but one of the most common is the 3x1 set. That features an "iso" receiver to one side, an outside receiver to the other side and two slot receivers closer to the formation.

When you watch teams such as the Cardinals, Packers and Patriots use the double-slot concept, the idea is to get a favorable matchup with a bigger, more physical receiver (and a smaller, quick target).

The Cardinals will put, say, Larry Fitzgerald and John Brown in the slot together. The Packers like to team Randall Cobb and Jordy Nelson there when both players are healthy. In New England's case, the bigger receiver can be tight end Rob Gronkowski, and good luck covering that.

Within that framework, offensive play designers have come up with different in-slot formations to make things more difficult for defenses. A recent favorite is to put the two slot receivers in a stack formation anywhere from one to three yards outside the formation and have them run crossing combinations at the snap.

If you have the outside receiver running a vertical route to take away the outside corner and influence the safety to that side—and one of your slot receivers running an intermediate or deep seam route to take the slot defender or linebacker—the other slot receiver running, say, a shorter out route is virtually guaranteed to be open.

Defenses can counter by bracketing coverage and handing receivers off, but when receivers run "levels" concepts in which there are short, intermediate and deep receivers to the same side, it's hard to cover everyone. That's especially the case if crossers are involved and the quarterback is on the same page as to who's going where.

The philosophy of the double-slot concept is the same as most new and evolving play designs in the modern NFL: It's a matchup league, and it's all about creating advantages in numbers and angles.

— NFL1000 Lead Scout Doug Farrar

Slot/Fade and Hitch/Seam

A coach's job is always to adapt to his players. As a new generation of players comes in, necessity has bred creativity and forced offensive coaches to dip into the college ranks for play concepts.

Doug Pederson and the Eagles are at the forefront of one passing concept renaissance: slot/fade. The fade route is normally perceived to be a red-zone route, but it has much more potential than that.

While at North Dakota State, quarterback Carson Wentz ran slot/fade often, both under center and out of shotgun. Slot/fade requires the slot receiver to run to get vertical while drifting toward the sideline. The outside receiver to the play side will run a route to hold the cornerback near the line of scrimmage.

Slot/fade works best versus man coverages. By alignment, the slot receiver's vertical push toward the boundary leads him away from a center-fielding safety playing over the top, as would be the case against Cover 1.

When coupled with the outside receiver taking the cornerback out of the picture, the slot receiver should have plenty of space to work with near the boundary between the deep-middle safety and the line of scrimmage. The route is also set up well to be thrown back-shoulder.

Wrinkles can easily be added to slot/fade, too. Rather than have the outside receiver just sit at the line of scrimmage, he can run a shallow or slot route. The quarterback then has another passing option while maintaining the core goal of slot/fade.

Teams have also found success with a similar concept with Air Raid roots. Hitch/seam is an Air Raid staple. Look all around the Big 12 and Pac-12, and you will notice it immediately. If you want to see it in the NFL, look no further than John Morton's offense with the Jets.

Hitch/seam requires the outside receiver to run a five-yard hitch route, while the slot receiver to his inside runs a vertical route down the seam. It is similar to slot/fade but is more intended to attack the deep middle and the flat rather than the deep boundary. Better yet, it is a more versatile concept than slot/fade. 

Hitch/seam can be an aggressive play or a "stay on schedule" play, depending on the coverage.

Most coaches will teach quarterbacks that if the defense is giving the hitch, throw the hitch. Off-man coverage and conservative zone shells lend to the hitch being open, so long as the quarterback gets it out on time. It should be an easy handful of yards.

When defenses are playing match coverages, it is time for the seam route. The seam player should be able to work vertically, either finding a crease between two deep-third players or running one-on-one versus a deep safety who matched him up in a 2-Read or Quarters-style coverage.

These spread concepts are not going anywhere. Slot/fade and hitch/seam, in particular, are easy to install, teach and tweak. The best offensive minds in football will continue to evolve these concepts, as they always do, and continue to use them to torment defenses for years to come.

— NFL1000 Linebacker Scout Derrik Klassen

Offset-Stack Formation

Over the past several seasons, the NFL has utilized more of the short passing game to carry offenses.

The league has transitioned from the deep passing attacks that were popular in the early 2000s. A number of factors have contributed to that, such as poor offensive line play, better pass-rushers and more spread offensive concepts.

Because of this new style of play and with so many teams building their offenses around the short passing game, defenses have adjusted by playing their cornerbacks closer to the line of scrimmage and jamming receivers to disrupt the timing of an offense.

One way teams have countered the increased press coverage is by using the offset-stack formation. It has been made popular this season by Sean McVay and the Rams, and it's a huge reason why they are the top offense in the NFL.

If an offense wants to avoid having a certain receiver face press coverage or if it needs to get a receiver into his route quickly, it can use the offset-stack formation.

One receiver will line up behind another receiver, who will be on the line of scrimmage. We have seen Chip Kelly in college and in the NFL use the stack formation frequently, but in this case, the "other" receiver is lined up slightly to the left or right of the guy ahead of him.

The spacing it provides is a big plus.

By running receivers out of the offset-stack, it almost always forces defenses to play off coverage because they are afraid of the chaos it creates. There is no way to press the receiver who is lined up underneath, so teams are forced to back off, allowing the underneath receiver to get a clean release off the snap.

However, there are disadvantages. Usually, these stacks come in a tight formation near the offensive line. That alone means there is more congestion in the middle of the field, making it harder for teams to run the ball.

But with all the positives it can bring to a quick, precision passing offense, the offset-stack formation is here to stay.

— NFL1000 WR Scout Marcus Mosher

Three-Man Rush

The three-man rush is not popular, both in regard to the approval ratings of armchair quarterbacks and in terms of how frequently the plays are called in the NFL. Still, only sending three of your 11 defenders to generate pressure on a quarterback is gaining more traction.

If you're an avid college football fan, you know it's almost impossible to overlook how often three-man pass rushes are being used on Saturdays against Pac-12 and Big 12 offenses. At the college level, where the long side of the field could be around 35 yards wide at times, defenses have to, for survival, only rush three defenders so they can drop eight defenders into coverage on any given play.

In the NFL, the purpose is much different. It's not so much that defenses don't have the defenders who can cover from sideline to sideline, it's that high-end quarterbacks are too good at picking apart coverages for four to eight yards a clip that more defenders are needed to crowd shallow zones.

Typical pass rushes feature four to six defenders on a blitz, which may not sound like much, but that only allows for seven to five defenders to drop into coverage against five potential targets in the passing game.

Football Outsiders noted that New England, by far, had the highest percentage (24 percent) of three-man pass rushes in 2016. For the Patriots, dropping eight players into coverage meant a bend-but-don't-break style that limited scoring, even if giving up yardage, while also allowing the clock to run. The overall idea was not much different than a prevent defense, even if it was watered down.

In Week 1, we saw the Chiefs use a three-man pass rush against the Patriots offense in a shocking 42-27 win. The Chiefs elected to drop more players in coverage instead of allowing Tom Brady to pick them apart in the quick passing game in crucial moments. That's a refreshing change of pace after seeing years of Brady and Peyton Manning (statue passers) tearing up blitzing AFC defenses.

The result? Brady, who is currently the MVP favorite in plenty of sports books, was limited to a 70.0 passer rating over 36 pass attempts. It was his only passer rating under 80.0 of his 2017 season so far.

The three-man pass rush may be as aesthetically pleasing as the end-zone fade, but with how it is evolving into a standard front at the college level and both a pseudo-prevent defense and a mentality to embrace against high-end quarterbacks, don't expect it to go anywhere.

— NFL1000 DL Scout Justis Mosqueda

Pattern-Matching Coverage

The simplest way to describe pattern-matching is that it's a mixture of the two extreme strategies of man and zone coverages.

As man coverages expose cornerbacks to potential one-on-one mismatches, zone schemes can be too easy to attack, either underneath or down the seams as the gaps in the defense become predictable to veteran play-callers and quarterbacks.

The way defensive strategists overcome these limitations is having their secondary drop into zones until receivers show their routes and then pick up their target in man based on predetermined rules.

This isn't a new scheme in 2017, but the prevalence of Cover 4 pattern-matching has been notable. If you've seen a deep post going for an open touchdown, such as T.Y. Hilton's score against the Texans, chances are the defense was trying to pattern-match but the corner failed to carry the receiver deep on the post because he expected the safety to help.

Meanwhile, the safety read the tight end or slot receiver taking a vertical release for a deep out on a flood concept and is now playing man on that target. That miscommunication has been responsible for numerous breakdowns this season already.

Even with the potential negatives in mind, coaches such as Bill Belichick, Pete Carroll, Nick Saban and Vic Fangio have made careers by building their defenses around pattern-matching.

Having a cornerback such as Richard Sherman, Xavier Rhodes and now Marshon Lattimore makes it possible to consistently run Cover 4 pattern-matching principles because they're dominant enough mentally and physically to be in position and understand the defensive reads almost every time. If executed correctly, the defense can suffocate intermediate and downfield passing lanes and dictate how the offense will play.

The Patriots defense has improved since early in the season as the breakdowns between their safeties and corners have all but disappeared. The Saints have become one of the better defenses in the league and no longer allow easy deep completions. As the 8-1 Eagles have worked to overcome a limited personnel group at cornerback, pattern-matching has allowed their pass rush to still be effective while not fully exposing their young corners to pure man assignments.

Of the top teams record-wise, the Chiefs, Panthers and Steelers are the least reliant on pattern-matching. The Chiefs rely mostly on man, while both the Panthers and Steelers are zone-heavy to protect their more limited secondary.

It's possible one of these teams bucks the trend of effectively using pattern-matching as a critical secondary theme, but most of the top teams have bought into it.

— NFL1000 Defensive Back Scout Ian Wharton