You're a new head coach planning to install your preferred offense and defense. Maybe your offensive coordinator runs a spread-to-run attack, while your defensive coordinator favors two-gap linemen.

How do you find the right athletes for your systems?

We've simplified some of the main schemes currently in vogue in college football today and provided you, the reader, with some details on what a school's roster needs to look like to accommodate the needs of those schemes. Which defenses or offenses require which kinds of players? Are there advantages or disadvantages to being a 3-4 teams vs. being a 4-3 team? How many wide receivers do pro-style teams need?

The most basic thing to know about college roster composition: teams at the FBS level have 85 scholarships to use. Teams also have walk-ons, but those aren't usually players much will be expected of. The most balanced use of those 85 scholarships is something like this:

Unit Scholarships Offense 41 Defense 41 Kicker, punter, long snapper 3

The numbers won't be exact for every team, but that's beside the point. How teams distribute those scholarships within the units is where things get interesting, both in terms of player types and in sheer numbers.

Note on roster breakdowns: We looked at the rosters of teams that run schemes included in each group while coming up with these numbers. Obviously there's a disparity from team to team and from scheme to scheme within the larger groups. For example, Georgia Tech had 14 running backs carry the ball last year, while Auburn had only five, and yet we've counted both in the same scheme group. Exact scholarship numbers are also hard to pin down without very close inspection, since teams also list their walk-on players.

4-3 defense

The 4-3 demands disruptive defensive linemen. Mike Carter, USA Today

Four defensive linemen, three linebackers, and four defensive backs. But it's not necessarily that simple.

In Big 12 country, for instance, no one really runs three linebackers out on the field, instead preferring a full-time nickelback who plays the wide side of the field or stays with the most dangerous slot receiver. However, 4-2 nickel defenses around the country are fundamentally 4-3 defenses, just with personnel adapted to defend the spread.

In this exercise, a 4-3 team is one that utilizes four down linemen playing classic one-gap, block down/step down rules on the defensive line and relying on fundamentals up front. A team that plays three down linemen with a stand-up defensive linemen, but following traditional 4-3 rules, still counts here as a 4-3, with the 'tweener player counting as a defensive end.

4-3 roster breakdown

Position Target size Target speed Scholarships Defensive tackle 6'1-6'4, 280-300 Quick off the ball Six to 10 Defensive end 6'2-6'6, 240-280 4.6 to 4.8 Six to 10 Inside linebacker 6'2-6'4, 230-250 4.6 to 4.8 Three to six Outside linebacker 6'0-6'3, 210-240 4.5 to 4.7 Four to eight Safety 5'10-6'2, 190-220 4.4 to 4.6 Four to eight Corner 5'8-6'1, 170-200 4.3 to 4.6 Five to 10

The 4-3 defense relies on strong play by the defensive line in controlling run gaps and rushing the passer without having to make heavy use of the blitz. These defenses will also tend to drop down a safety to create an eight-man front and consequently put a burden on the cornerbacks to hold up with less deep help.

The advantages in recruiting to a 4-3 system include its widespread use both in the high school ranks, increasing the pool of prospects, and the NFL, allowing recruiters to sell professional development. If the defense is strong up front, the system allows all kinds of athletes to roam the back seven. A 4-3 team will thrive with great linebackers, but what those players can look like is determined by the front.

The disadvantages in the 4-3 are finding those difference-makers up front, particularly multiple 290-pound defensive tackles who can rush the passer.

3-4 defense

The 3-4 enables pressure from every angle. Bob Stanton, USA Today

For the purposes of this article, any team that utilizes two-gapping techniques up front will count as a 3-4 defense, even if they play frequently four defensive linemen, as Alabama frequently does against one-back teams.

3-4 roster breakdown Position Target size Target speed Scholarships Nose tackle 5'11-6'5, 290-340 Non-slow Three to six Defensive end 6'2-6'6, 270-310 Quick off the ball Six to 10 Inside linebacker 6'0-6'3, 230-250 4.6 to 4.8 Five to eight Outside linebacker 6'1-6'5, 220-260 4.6 to 4.8 Five to eight Safety 5'10-6'2, 190-220 4.4 to 4.6 Four to eight Corner 5'8-6'2, 170-200 4.3 to 4.6 Five to 10



The 3-4 defense has a similar feature to the 4-3 defense: it asks the line to do much of the heavy lifting and thus frees up the rest of the team. This scheme is different from the 4-3 in that the two-gapping technique by the line will often allow a team to widen its linebackers to handle spread teams' spacing and keep its safeties deep and free of run responsibilities.

Additionally, the three-man line lends itself to blitzing and disguise and can get a pass-rush from different positions on the field without relying on a dominant pass-rusher, because a 3-4 team bring linebackers from whichever angle is likely to generate pressure against a given opponent. Finally, the fact that linebackers don't have to put their hands in the dirt and line up across from a massive offensive tackle allows teams to use explosive pass-rushers without ideal measurables.

The difficulty is in finding those three big guys up front. Ideally, the ends can collapse the pocket and create a three-man rush. Those ends are often somewhat like 4-3 defensive tackles in size and skillset, making them among the harder positions to find and recruit, although they don't have to be quite that big.

Then there's the nose tackle, tasked with controlling the interior lanes from guard to guard, an assignment that requires massive strength and ability. Outstanding nose tackles are among the hardest players for many schools to find.

3-3-5 defense

Seems easy to block, right? Land-Grant Holy Land

In this article, consider the 3-3-5 as a catch-all term for defenses that put maximum speed on the field and rely primarily on movement and stunting up front, rather than the 3-4 front's focus on two-gapping. A 3-3-5 defense's best weapon is disguise, and they often rely on playmakers on the back end.

And, as with all other defenses, the 3-3-5 is a base defense for some teams, but only a situational modification for others.

3-3-5 roster breakdown Position Target size Target speed Scholarships Defensive linemen 6'0-6'5, 270-310 quick off the ball Eight to 12 Linebackers 6'0-6'4, 220-250 4.6 to 4.8 Eight to 12 Overhangs 5'11-6'2, 190-220 4.4 to 4.6 Five to seven Free safety 5'10-6'2, 180-210 4.3 to 4.6 Three to five Corner 5'8-6'1, 170-200 4.3 to 4.6 Five to 10

Defenses like the 3-3-5 can overcome the difficulties in finding the defensive linemen that are so essential to the 4-3 and 3-4 defensive structures. These teams are typically looking to find quick linemen of adequate size who can move around and frustrate an offensive line's blocking assignments. The zone blitz is a common tactic for achieving this.

"Overhang" is one term for the 3-3-5's safety/outside linebacker hybrids who roam the flats, blitz the edges, and support against the run. One recruiting advantage: these players can be fashioned from too-big defensive backs and too-small linebackers overlooked by other systems.

Because these teams will move around their linemen to create advantages, that puts pressure on the back end to clean things up when ill-timed or poorly executed blitzes open up holes in the defense. The linebackers in this system have to fill the lanes behind the DL with precision to avoid creases and also be explosive enough to take advantage of pass-rushing opportunities.

In order to bring pressure, these teams also tend to put a lot of responsibility on the corners to hold up on islands and on the free safeties to prevent long runs, passes, or yards after catch.

Spread-to-run offense

Spacing, dual-threats, oddball offensive linemen, and distribution to lots of ball-carriers are among the spread principles used by option-run offenses. Danny Wild, USA Today

The spread is an ubiquitous term that essentially boils down to using widely spaced formations to exploit isolated defenders, which could be done either through the passing game, running the ball, or both. For this article, teams that use the option, run their quarterbacks, and are primarily looking to run the ball outside of pro-style sets will count in this category.

Spread-to-run roster breakdown Position Target size Essential skills Scholarships Running back 5'8-6'2, 180-230 Pure runner Five to nine Quarterback 6'0-6'4, 210-250 Quick making reads, dangerous as runner Three to five Tight end/fullback/H-back 6'0-6'5, 220-260 Run blocking, hands softer than stone Three to five Inside receiver 5'8-6'2, 170-210 Dangerous in space Four to eight Outside receiver 6'0-6'4, 200-230 Willing blocker, dangerous downfield Four to eight Offensive lineman 6'1-6'5, 280-340 Run blocking 14 to 18

Spread-to-run teams are built largely around their ability to create opportunities for their backs to find seams, get to the second level, and get chunks of yardage.

Offensive line play is of course important, but the lessened onus on pass protection means that these teams can often target linemen who wouldn't fit in another system. For example, the shorter, lighter lines favored by flexbone teams can thrive by getting low and driving people, getting out in space as pullers, and throwing cut blocks on the backside.

One advantage to recruiting for these schemes: sophisticated skills are less essential.

One advantage to recruiting for these schemes: sophisticated skills are less essential. So long as a spread-to-run team has players at receiver, running back, and quarterback who can do damage with the ball in their hands, the scheme affords numerous ways to do so that don't involve complicated passing patterns, timing, or great receiving skills. The rest of the roster can be geared towards finding brutes who like to knock people over and out of the way.

The quarterback is a cornerstone, but he needn't necessarily have typical attributes in the passing game. He does need to be able to make quick and effective decisions distributing the football (whether by pass, pitch, or mesh) and pose a credible threat when his reads tell him to keep the ball himself. If the quarterback is not a truly dangerous runner, the backs and receivers had better be.

Disadvantages in finding players for this system include selling players on strategies that won't be widely employed in the NFL and finding ball-carriers worth featuring in great enough numbers to survive injuries. A spread-to-run team can be crippled when its explosive quarterback is injured and the back-up is less athletic or less familiar with the system, but that goes for every system.

Spread-to-pass offense

The quick, efficient, wide-open passing game is alive in Texas. Michael C. Johnson, USA Today

This was once an easier category to define. Run 'n' shoot and air raid offenses were far more pass-happy until the Art Briles and Dana Holgorsen coaching tree took over. Teams with air raid systems began to put greater emphasis on the run game.

For this article, those spread teams that primarily emphasize the passing game will count as spread to pass teams. Obviously there is overlap, and some teams like Baylor have the flexibility to drift back and forth based on their personnel. These teams will be defined for favoring complexity in the pass game rather than the run game with a preference for quick passing concepts.

Spread-to-pass roster breakdown Position Ideal size Essential skills Scholarships Running back 5'8-6'2, 170-210 Dangerous in space, able to catch and help in pass protection Four to six Quarterback 5'10-6'5, 200-220 Quick making reads, accurate Three to four Tight end 6'2-6'5, 220-260 Inside receiver Two to four Slot receiver 5'10-6'2, 170-210 Quick change of direction, acceleration Five to eight Outside receiver 6'0-6'5, 190-220 Route running, winning jump balls Five to eight Offensive lineman 6'3-6'6, 280-330 Pass protection, quick feet 14 to 18

Great spread-to-pass teams often look for athleticism from their quarterbacks in order to mitigate the need for great pass protection from the offensive line and to bolster the overall run game and playmaking potential of the system.

However, the true dual-threat quarterback is hard to find, and isn't considered essential for most passing teams. Plenty of teams have done plenty of damage taking quarterbacks ignored by other systems because of their lack of height, arm strength, or athleticism. The great advantage to the spread-to-pass systems is that the quarterback simply needs to be decisive and accurate; the scheme and playmakers around him can do the heavy lifting and gift him tremendous numbers. The spread-to-pass can succeed with a basic distribution quarterback (any Mike Leach passer), an athletic quarterback (Colt McCoy at Texas), or a quarterback who would've also fit into a pro-style scheme (Sam Bradford at Oklahoma).

The difficulty for this system is consistently surrounding the quarterback with difference-makers at the receiver positions and an offensive line that is athletic enough to get moving in space. These teams frequently run screens, and those only work with quick linemen.

Pro-style offense

The country's best 2013 offense used huddles, under-center snaps, a complex variety of passing routes, classic tight ends, and fullbacks. Grant Halverson, Getty

As spread concepts slowly seep in and take over the NFL (with the college and high school game already conquered) this term is quickly losing its meaning. When Peyton Manning is running a hurry-up, spread offense in the Super Bowl after beating a similar team in the AFC Championship, it's probably a good idea to pick a new term.

While someone else figures out what that term will be, we'll use pro-style to describe teams that are characterized by utilizing on-the-line tight ends and feature complexity and a level of difficulty in execution with both their run and passing concepts. Power-coast teams that blend together downhill, power-run schemes with West Coast passing offenses will fit here, as do teams that pound the ball on the ground before throwing vertical routes.

Pro-style roster breakdown Position Size Skillset Scholarships Running backs 5'11-6'2, 200-230 Physical, versatile Four to six Quarterbacks 6'1-6'5, 200-230 Strong arm, accuracy downfield Three to four Tight ends 6'3-6'6, 230-260 Run blocker, capable route-runner Three to six Wide receivers 6'0-6'5, 190-230 Route running, dangerous downfield Eight to 13 Offensive linemen 6'3-6'6, 290-330 Physically dominant, quick feet 14 to 18

For any system that's looking to physically impose its will on the opponent, the offensive line is the most essential unit to get right. Pro-style teams require linemen who can handle a pass-rush long enough for downfield routes to develop on one play and then bowl over a defensive front the next.

Because of the focus on execution in pro-style offenses, a stud playmaker at running back and wide receiver is essential. Pro-style teams are more likely to feature specific players, rather than get everyone involved.

The needs of the quarterback position depend on the scheme, but most pro-style teams are looking to punish opponents downfield with the passing game, which requires a level of downfield accuracy and arm strength that can be hard to find. You saw this approach attempted successfully and unsuccessfully at LSU with Zach Mettenberger.

After offensive line and quarterback, recruiting tight ends who can bolster both the run and pass is the most difficult challenge for a pro-style team.

2005 USC was perhaps the pinnacle pro-style collegiate offense.

Summary

While there's great overlap, each system has its own requirements and has to target particular types of players to find the blue-chippers that will have the greatest impact for the system. Transcendent players typically fit anywhere, but they aren't as common as some think, with only about 300 for the whole country every year.

Keep these notes in mind when evaluating your favorite schools' recruiting class and check to make sure they are loading up with the right players at the right spots, regardless of the star ratings.

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