If a John Chavis defense and Texas A&M's air raid can coexist, look out

Playing tough defense is often one of the hardest challenges for offense-oriented teams, especially squads built around strategies like the air raid. It puts a premium on developing the passing game while sometimes treating the run as a constraint to be called upon if the pass isn't working.

That approach doesn't always produce the kind of hard-nosed defense that can carry a team if the offense is down.

For Kevin Sumlin's air raid teams at Houston and A&M, the defenses, especially on the ground, have failed to carry their weight. They have often been Achilles heels that have prevented top offenses from generating better results in the standings.

A quick look at Sumlin's defenses as a head coach, ranked by Football Outsiders' overall S&P and rushing S&P, makes the Aggies' priority clear:

Year	Team	S&P	Rushing
2008	Houston	66th	72nd
2009	Houston	100th	108th
2010	Houston	79th	98th
2011	Houston	65th	84th
2012	Texas A&M	9th	8th
2013	Texas A&M	76th	77th
2014	Texas A&M	73rd	110th

Defensive coordinator Mark Snyder was able to get real results from the 2012 Aggie defense he inherited from Tim DeRuyter. That fell apart after he lost crucial seniors from the defensive front. Since, Sumlin's Aggie teams have resembled his Houston ones.

Playing in the SEC meant a floundering run D would inevitably result in devastation and ruin.

Opponent	Rushing S&P rank	Yards vs. A&M	Yards per carry vs. A&M
South Carolina	14th	67	3
Lamar	N/A	90	2.4
Rice	100th	240	4.4
SMU	80th	102	2.4
Arkansas	26th	285	6.1
Mississippi State	10th	280	5.6
Ole Miss	49th	160	4.6
Alabama	8th	298	6.6
UL-Monroe	126th	78	2.6
Auburn	16th	363	6.2
Missouri	43rd	335	6.8
LSU	29th	384	6.7
West Virginia	79th	126	3.9

With the exception of the wildly inconsistent Gamecocks, every team with a pulse was able to run, some of them right down the Aggies' collective throat. For a team that relies on tempo, this can easily result in the opponent dominating time of possession, exhausting the defense and denying the offense the chance to take over the game.

The problem

The Aggies lacked top-flight run defenders at most every position, but their main problem was up front.

There are two routes to having a strong defensive front. One is to have linemen who will dominate an opponent if they aren't carefully double-teamed, supported by linebackers who know how to take advantage when playing behind great protection.

Another is to have linebackers who flow hard to the ball and will wreck everything if they aren't accounted for, leaving the offense with less time to control the defensive line.

Both can allow a defense to prevent running backs from accelerating to the second level. Most teams have to aim for formula No. 2, as quick-reacting linebackers are easier to come by than dominant defensive linemen.

A&M had neither. Its young crop of linemen was filled with players who could scarcely maintain interior gaps, much less get into the backfield against the run. The linebackers consisted of several players who were either too inexperienced or too slow-processing to aggressively fill behind them.

The result? Running lanes opened up easily, which forced Snyder to employ aggressive safety alignments to try and clean up plays that slipped through.

On this play, the Aggies are in an eight-man front with the strong safety close to the line of scrimmage. The free safety is also in a fairly tight alignment to provide a ninth defender if things get messy. The Aggies are playing LSU, so of course things get messy.

How it really goes bad for A&M is that not only do the weakside end and linebacker fail to close off any lanes, they don't even execute their assignments correctly.

There are two ways to defend this inside zone with a slice/trap block, which looks to create a running lane between the defensive end and the double team of the backside tackle.

One answer is for the end (right E, below) to step inside and wait to meet the trap block (F) on the inside. That would spill the ball carrier outside, where the weakside linebacker or secondary guys can make the tackle. That seems to have been what the weakside linebacker was expecting to happen.

Another route would have been for the end to play the trap block outside-in, so as to take away the edge while counting on the weakside linebacker to fill the resulting gap. The end needs to squeeze that gap as small as possible.

Star freshman end Myles Garrett performed neither of those tasks, instead trying to make a play in space and getting cut down while Leonard Fournette flew through. Free safety Howard Matthews did a credible job of cleaning up mistakes and finished the day with 15 tackles, but if you ask your safety to meet Fournette in the alley, you're going to get results like this sometimes.

Garrett is a brilliant player in space. He's a devastating pass rusher, No. 5 in the country in sacks per game. He's capable of stepping inside on read plays to encourage QB keepers, then stopping runners as fast as Auburn's Nick Marshall from winning the edge. But when it came to playing blocks in coordination with the rest of the front, Garrett was a liability targeted by multiple opponents.

LSU went after him with play action, sent the fullback on a banana route, or used zone read plays with the fullback arcing around him to block the linebacker. It all worked. There was no coordination between the first or second levels. Garrett finished with one solo tackle and rarely set up the players behind him for success.

Teams loved pounding the edge, where lack of discipline combined with occasionally suspect DB assistance to create big opportunities, but there were problems up main street as well.

On this play, Auburn completely drives A&M off the ball. When the tailback gets the ball, he's already looking at a massive hole.

There are some real athletic talents in the Aggie front seven and a few more on the way, such as five-star defensive tackle Daylon Mack. It's simply hard to stop the SEC's more potent running games if your most talented front players are underclassmen.

The lack of coordination and development cost Snyder his job.

The solution?

Defensive tradition is important at A&M, where the most beloved teams of the '80s and '90s were defined by the Wrecking Crew defenses of Jackie Sherrill and R.C. Slocum. The Corps of Cadets and semi-militaristic culture of the university beg for a team that will smash opponents in the mouth.

In that regard, the SEC has proven to be a cultural fit. But they've had to compromise their identity to welcome Sumlin's exciting brand of fast-paced football that will throw all over a team before thinking about putting the ball on the ground.

That compromise cannot extend to having a soft defense. Sumlin moved to fill that gap by hiring LSU coordinator John "Chief" Chavis, whose defenses finished in the top 15 in Football Outsiders' F/+ four times since 2010 and in the top 10 in rushing S&P four times since 2009, including No. 1 in 2011. In a shrewd move, Sumlin thereby removed the coordinator who'd caused the Aggies' offense the most trouble over the years.

Chavis' defenses at LSU were defined by absurd athleticism across the two-deep, which resulted in players leaving early for the NFL, combined with simple schemes that allowed that talent to play fast. A&M's collection of talented East Texas and Houston athletes are cut from a similar cloth. He'll find a defensive front with athletes like Garrett, Mack, Zaycoven Henderson and Otaro Alaka.

Where things get interesting is at defensive back.

Chavis was one of the early coordinators to realize playing nickel and dime personnel who could challenge receivers would allow him to keep run stoppers in the middle at safety and linebacker. Consequently, he loaded the Tiger roster with long, quick cornerbacks. That allowed 4-2-5 or 3-2-6 packages with big inside linebackers and downhill safeties like Craig Loston or Jamal Adams. Aligning them in the middle meant avoiding difficult coverage assignments.

Texas A&M's recruiting over the last two classes has not quite matched that design.

Year	Player	Size	Projected position
2014	Armani Watts	5'10, 190	Free safety
2014	Nick Harvey	5'9, 180	Nickel/corner
2014	Donovan Wilson	6'1, 192	Strong safety
2015	Roney Elam	6'3, 175	Corner/safety
2015	Justin Evans	6', 185	Nickel/safety
2015	Justin Dunning	6'3, 204	Safety
2015	Larry Pryor	6', 196	Safety
2015	Deshawn Capers-Smith	6', 173	Corner

This group doesn't feature many long coverage players of the sort Chavis thrived with at LSU. Harvey and Evans might thrive in the nickel role that has featured stockier players like Tyrann Mathieu, but only Elam or perhaps Capers-Smith -- if he plays defense -- fit the mold of lanky press corners.

There is hope that this group will provide better run support at safety than the Aggies have grown accustomed to.

Overall, Chavis is going to need time to mold the young Aggie front into a coordinated group that gets the most out of its athleticism. He's also going to need to remake the roster by grabbing more coverage players, allowing him to outnumber the run and pack the middle of the field with big athletes.

At LSU, Chavis was aided considerably in that developmental process by Les Miles' hard-nosed culture, which includes one of the most brutish versions of manball offense the modern game has seen. Every day, Chavis' top-notch athletes went up against massive run game personnel, which won't be the case in College Station. Will that matter?

Whether A&M can take a long view in Year 4 of the Sumlin era while trying to build a brand as the preeminent football power in the state of Texas remains to be seen. What also remains to be seen is whether the problems stopping the run over the years are a result of Sumlin's hires or his culture.

With Chavis and the talent on campus, Aggie fans should know before 2016 is over whether the Wrecking Crew is a revitalized tradition or a sacrifice to Sumlin's brand of football.