PRESHA

Gratuitous clips of 2009 NFL sacks

2009 CHI SACKS 1 @ Yahoo! Video

2009 CHI SACKS 2 @ Yahoo! Video

2009 CHI SACKS 3 @ Yahoo! Video

2009 NO Saints Sacks 1 @ Yahoo! Video

2009 NO Saints Sacks 2 @ Yahoo! Video

Fundamentals: Defensive Backs

Ran across some great fundamental drills for honing man-to-man skills recently.

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Very basic stuff, but the simplicity of repeating leverage on receivers in these drills and reinforcing the concept (and avoiding the unnecessary movements) is something to take away from these.

Good luck this season.....

Review: HUDL

AWESOME

Easily the most efficient, cost-effective, and user-friendly video system any school could ask for. With packages running from $800 - $1600 (based on storage needs), your program can open up the world of film study and game access available to anyone investing in your team.

You can eliminate the spindles of DVDs needed in a season for trades, cuts, film study, and weekly distribution (scout & last game) because everything is housed online on HUDL servers.

As new customers, we have been toying around with the product for a few months and although most on staff are not techno-philes, everyone can use the system because it is no more difficult than a remote control.

Once the game film is uploaded, it will parse into play segments for the staff to detail (as little or as much as you like) later. You can upload game film, scout film, practice film, anything you want.

With the game film online and telestrated/commented as you like, you can distribute it to other coaches, to players, to parents, or even college recruiters.

The only thing required is to have MS Silverlight (Gates' version of Flash) installed on the PC to view the applet.

We plan on (and have been for spring) using this during the athletic periods (football class) to dial up situations pertinent to the game plan or teaching plan. This eliminates the need to cutup the game film and burn to discs for special presentation the night before. Just toggle the plays you want to review and its there in an instant.

There have been tons of video editing, databasing, scouting, and storage solutions offered in the last 8 years in the coaching industry, but nothing captures the full spectrum of needs like HUDL. Be sure to check out the current offer before the season starts!

http://www.hudl.com/blog/comments/test-drive-hudl-i-promise-its-free

I would have to say, one of the coolest aspects of HUDL, isn't the program itself, but the customer service. If you have a problem or question, just call their support line and you will actually talk to a real person (that knows the product). If they can't walk you through it, they'll remote desktop into your PC and fix any issues you might be experiencing.

Nebraska Pressure: 7 Man Blitz

After reviewing their base front, fire zone and dime package, now we'll explore what happens when offenses dictate nickel (substitute a Nickel back for the Buck) based on medium passing downs or 10 personnel package.

In the glory years of the Tom Osborne-era Huskers, the Blackshirts and Charlie McBride lived in what they called "11 Robber". While we'll touch on that in a later post, it essentially was Nickel Cover 1 (1 high MOFC player, 1 low hole player). Because of the matchup advantages in the secondary and the versatility in personnel, these new Blackshirts thrive on bringing maximum heat when in Nickel.

Much like the spinner grouping, Pelini has a preference on bringing pressure, rather than sitting back in coverage or even fire-zoning offenses.


The easiest way to generate maximum pressure on quarterbacks is Cover 0. Every defender accounts for a receiver, and those without will pressure. This concept should not be discounted because of its insane simplicity.

In their most often used pressure concept when in Nickel, is "Over Loose Bomb Blitz".

This is essentially the 'bonzai' blitz from the Jim Mora 49ers playbook that is bringing both safeties. This is perfect against 2-back sets, but is certainly sound against 3x1 or 2x2.

Corners are playing catch-man technique with a 9 yard cushion, able to jump hot throws and deep enough to maintain an over-the-top leverage on deep receivers.

Both safeties will present the 2-high look (like every snap), then begin creeping once the quarterback begins the cadence. They are both attacking the 'B' gap. The interior tackles collapse the A gaps to open this overload blitz in B gaps. This direct and immediate pressure will force quarterbacks to take unnecessary hits and at best scramble into contain players.


The ends will play the common "peel" technique (as covered previously) against any back flow, and inside-out leverage an flaring action. Versus empty, the ends will have no responsibility but to rush the passer.


Take a look at these clips to get a better perspective of how simple and effective a Cover 0 - check blitz is.




On a personal note, I would like to add that even though being a "defensive-guy" and being a coordinator who is not big on man-to-man, that if you do not have a Cover 0 check blitz in your package, you are really missing out. It can be installed within minutes, disguised from any look, and provides a 'cheap' answer during a game that falls outside your game plan. I would certainly encourage any defensive staff member to look at the 'check-blitz' not as a way of life, but as something up your sleeve to before your first game. It is a great way to jump start your defense into winning conversion downs and build the confidence in the team in the early stages of the season.

Spacing...The Final Frontier - part 4

The final read in the Spacing progression is the Flat route.  This is a 2003 Toledo cut-up when Rob Spence was the OC there.  The frontside X WR has a Speed Out.  The QB sees the CB up tight initially and decides that the Speed Out will not be not there.  The QB should have stayed with this route because the CB was bailing out, albeit slowly.  The depth of the CB is one consideration for the QB's pre-snap read; the other consideration is the presence of an alley player.  The nearest LB was not in the alley, but was tucked in the box, so he was not a threat to the route.  The alley is defined as the area between the X WR and the OT to a depth of 8 yards.

If there is no one in the alley, this is considered a Premium look.  Although this was a Hard Access (no alley player and a "Hard" CB within 6 yds) look initially, it became a Free Access (no alley player and a loose CB) look to the X WR.  Defenses like to disguise their coverages to confuse the QB's pre-snap read, so it is important for the QB to get a post-snap read and follow through on his progression by looking to the X WR first. 

Free Access is the look that the QB wants to see from the Defense.  Many teams put their best WR at the X position so they create these Free Access looks and isolate their main guy 1 on 1.  This is done by overloading the opposite side of the formation with Trips or Bunch formations, as Toledo does here. 

The OL is using Slide protection to the right with the RB blocking the first thing off the left edge away from the slide.  The use of motion in Spacing can be an effective way to disguise the play initially, since a compressed split is needed by the WR to get to his spot on the Mini-Curl route, which is roughly 4 yards outside the OT.  The WR also could get to his spot here by running his route in at a 45 degree angle. 

The QB also could have thrown to the Sit route if he puts the ball on the opposite shoulder of the defender.  The Mini-Curl is double-covered, leaving the Flat route wide open.  Florida QB Coach Scot Loeffler said at the 2009 Florida Clinic that the Flat route should be run at "golf-cart" speed--fast initially, and then choke it down.  He wants to be fast initially to get past the Mini-Curl's route and make the Flat player on Defense commit.  The flat player cannot cover both in Cover 3 if the "spacing" is right.  It is important for the Flat WR to choke it down so he doesn't run out of bounds and has room to run up the sidelines.  The FB running the Flat route choked it down, but the QB led him a bit too much on the outside, making it hard for the FB to stay in-bounds and get upfield. 

Spacing (to Flat route) @ Yahoo! Video

This concludes the Spacing series.  Click on the Spacing Label below if you would like to see the previous posts.

Nebraska Pressure: 3 Seam (5 Man Zone Blitz)

So far we've covered Nebraska's base front and adjustments, along with their special dime package for pressure. In this segment, we'll look at how they bridge the gap between base zone coverage and man coverage rules, with the fire zone.

Now, it should be noted that Nebraska doesn't rely on the fire zone nearly as much as many other NCAA defenses. It does provide them with a sound concept against every offensive formation with 5-man pressure. In this post, we'll take a look at their most used blitz and the coverage rules behind it.

Pelini supports all his fire zones with the 3 deep 3 under coverage known as "3 Seam" which simply declares that there will be 2 Bronco players and 1 "final 3" player. The only question remaining is who will fill those roles.

We'll look at the package "Strong Go", which is simply the standard "NCAA Blitz" fire zone. Nebraska will primarily only use this blitz against 10 and 11 personnel. Believe it or not, along with Boston and Frisco concepts, this fire zone package is also installed in the first day of fall camp (with a different fire zone package installed each day thereafter).

This is a strong side / passing strength overload based out of the Frisco family, that is adjustable and sound against any formation. The tight end is matched inside, outside and vertical by the hole, SCIF, and deep hole player, eliminating any hot to him.

The pressure side end long sticks to the “A” gap opening up a lane in the “B” gap for the Mike. The away end becomes the potential dropper, playing run until pass shows, then bailing to take away any hot into the seam. The corners play 3 bail and are man-conscious on #1. From a 2-high shell the safety to the pressure side drops on top of #2 as a SCIF/Bronco player.

The concept remains sound against Trips / Trey looks and just walks the Buck out on #2 and effectively sends pressure from the passing strength.


Even with a formation reset or a called Boston (Over) front, the concept is solid (set to the passing strength). The pressure comes from the passing numbers side, almost egging a quarterback to throw a hot to #2, who is about to be robbed by the dropping Bronco safety.

As we covered earlier, for every concept installed, a counter-concept is introduced. In this case, instead of a passing strength pressure, the opposite would be a weak side blitz, known as "Flex Go", always run out of the Boston (Over) front. Instead of blitzing into a passing strength, "Flex Go" blitzes away from the passing strength.

If 2 becomes 1 (motion/shift) the safety replaces the Mike, and the Mike becomes the Bronco player to the pressure.

This provides an easy adjustment/answer to everything that can be presented on any given down. A simple breakdown of motion / shift checks out of this blitz looks like this:

• 2 (wr) becomes 1 (wr) = Flex (Buck / Safety)
• 1 (wr) becomes 2 (wr) = Strong (Buck / Mike)

In the example below, strength is set to the flexed tight end and Strong Go is called. This will bring the Buck and the FS (with a switch call on the Mike, who becomes the Bronco player).

The final 3 player is the Will, with the away-side end playing run, then dropping underneath the stem of the single split receiver. The field pressure forces the ball into the area where the end drops to (that the quarterback did not account for).




The very same concept can be applied to any front, with nothing new to teach. Shown here with the Spinner package detailed earlier:


Have you seen this concept before? Yes, you have.....
fire zones from the 2002 San Francisco 49ers playbook (3 Seam)


In our last installment of the Nebraska defense, we'll detail how they borrow from their past to generate maximum pressure on their opponents.

Nebraska Pressure: Spinner (6 & 7 Man Blitz)

In the first installment, we covered Nebraska’s base front and the base principles about matching fronts with their Buck linebacker. But what happens when your base defense and personnel are not the best tool for the job? What happens when you get in long-yardage situations or the offense gets out of 21 / 11 personnel? How does Pelini handle these special situations?

The spinner personnel grouping (3 DL, 1 Nickel + 1 Spinner) equates to a GATA package, and is premised on just that; getting after your ass. Whenever you see 3 DL in the game for Nebraska you can bet good money that they will likely end up in a 7 man pressure package supported by Cover 0. The most common concept Nebraska will use is known as “Steeler”.



This simply puts the corners and safeties on split receivers and everyone else is collapsing the pocket. This is the simplest pressure package in football and most known as the “Tigercat” blitz from Jim Bates (of 90's era Dallas Cowboys renown). The numbers will always afford for 1 free rushing defender (no matter how many stay in to protect, the defense will always to bring 1 more than they can block).


In spinner, the Ends will align head-up on the tackles to provide the threat of a 2-way go, though they will bull rush through the inside arm, to free up both the “C” gaps for Nickel/Safety edge pressure as well as help open the “B” gaps for Mike/Spinner blitzing. Versus 2 backs, the nose will always take the right “A” gap. Versus 1 back, the nose will bull rush the center. The edge rushers in this blitz have a "peel" assignment that allows them a free path to the passer unless the back releases to their side. In the event of a back release to their side, the rusher should peel off the rush angle and pickup the back in coverage from an inside-out leverage.

All coverage defenders are playing in an off-man or ‘catch’ position on receivers, allowing the receivers to free release. This prevents the coverage defender from giving up a deep throw, as well as, allowing the defender to keep his eyes on the ball, looking to break on the interception the minute the receiver sticks into his break.

If the slot matchup is better suited for a nickel / buck backer, the converse spinner adjustment is known as “thriller”. Exactly the same as "Steeler", with the exception of freeing up the safeties by engaging the Will / Buck ( substitute for Nickel) in coverage on inside receivers.



As a change-up and counter to the Cover 0 pressures, a rotating man-free concept is available provide a little more insurance behind the blitz and provide middle of the field protection.


The Back Dog pressure features an orchestrated overload to the Mike backer side of the ball. The Mike will be supported by a cross-facing nose (to open up the blitz lane), an end, and either the Buck Nickel or corner. The spinner will align away from the back, with the Mike to the back. The Weak Nickel will align to the tight end (or 4th receiver), with the Buc Nickel to the passing strength. This basic concept can be run based on personnel or field/boundary, the only adjustment (called from the safeties) would be from the blitzing corner or Buc Nickel.


Examples of Spinner Back Dog 1 Comet being run:

If you recall (or rewatch), during the Big XII Championship Game, after stalling Texas early in the 1st half, Pelini used his Spinner groupings to pressure McCoy all night into errant throws and interceptions.

This is the primary look Pelini will give once this dime grouping is introduced. He does have other coverage variations (next post) that apply to the base defense, but rarely utilizes them if nothing more than a change-up.

Nebraska Over / Under Front

After another exciting college football season in 2009, there weren't many stories that were as satisfying as the Nebraska Cornhuskers return to national significance with Head Coach Bo Pelini.

Lead by once-in-a-lifetime freak of nature, Ndamukong Suh, the Huskers dominated opponents through the season and narrowly missed an opportunity at a National Championship ( after completely dominating the explosive Texas Longhorn offense in the Big XII championship game).

With such a phenomenal athlete graduating, you'd be hard pressed to believe the defense in Lincoln could improve on such a performance. Think again....

With up-and-coming Sophomore phenom NT, Baker Steinkuhler (55), and his returning linebackers Will Compton (51) and Sean Fisher (42), this youth movement will prove to be a integral part of the Blackshirts rebirth in 2010.

In this post, we'll look at how the Nebraska base front sets the philosophy behind everything Pelini does. In subsequent posts, we'll look at the secret behind their overwhelming pressure and how it relates to these base defensive principles.

At the core of it, Bo Pelini has a made a name for creating fundamentally sound defenses that play fast, year in and year out. Among the signatures of these defenses is a dominating front 7. The fundamental concept behind this defense is his use of the Under / Over defense. This is a 7 man front, complimented by 8-man (front) principles (of bringing a safety down in support).

Pelini will install his entire defense within one practice. This simplicity affords built in answers to everything an offense can present, as well as a foundation to build off of for multiplicity.

Every offense, according to this philosophy, is determined by numbers. The key factor that swings numbers for the offense (at the point of attack) is the Tight End. Pelini spends a lot of time teaching identifying and explaining why teams get into those personnel groupings, then how to handle all adjustments. Once the defense recognizes what an offense presents, it can begin narrowing down the types of actions the offense can deliver in any given personnel grouping. For instance, "21" (2 backs, 1 TE) would predominantly run-centered defense, primarily geared to attack to the Tight End side. "11" personnel eliminates the threat of lead runs and is geared more to the passing game. With "10" personnel, they just need to determine if it is a pro or slot look. The entire defense is built off of where the TE is. So by identifying personnel groupings immediately after a play, the defense narrows their focus to determine if they have to look for a TE or a slot.

"Once you know the personnel you can anticipate formations by process of elimination.

• We treat 12 & 21 the same. In 12 we consider the U the fullback
• Vs. 21 think I-pro or I-slot.
• Vs. 12 think pro or slot pair.
• Vs. 11 we are thinking in terms of doubles (2x2) or trips (3x1) & since there is a TE they can still form a slot. We always go into a game with a check vs. slot trips
• Vs. 10 we are thinking in terms of doubles (2x2) or trips (3x1) & since there is no TE they can’t form a slot.
• Vs. 20 A pro set is the only formation that can be formed. Any change of strength motion, same as, “Y-TRADE.”

Fast accurate identification is very important because it gives the entire defense time to adjust. We usually go into a game with a number of automatic checks and adjustments based on formations. "

With a Tight end in a formation, the Under front allows the defense to match numbers by aligning a linebacker tight, outside the tight end. This gives the defense 4 defenders to a 3 man surface (neutralizing any offensive numbers advantage). Shown here is the under alignment:


The remaining linebackers are protected in the front with a 7 technique and 1 technique in a strong side bubble with the Mike. The common weakness in a tight end formation is the weakside bubble. The under front now covers up this liability with a 3 technique and 5 technique end. This alignment effectively covers up the bubble and protects the 10 technique Will linebacker.

To simplify things, Pelini categorizes his fronts into families, coded by east and west coast cities. Under is west coast, over is east coast. The Under family is based out of Frisco (Under Zone X) and Vegas (man) and its compliment is Boston (Over Zone Y) and Philly (man).



Pelini's defense will always align in a 2-high shell, to always present the same presnap look. Though presenting a 7 man front, the defense will drop the safety away from the Buck to serve as the backside contain player. This method known as "Lever-Spill-Lever" and through it, the defense evens up the numbers (gap fits) available with 2-backs in flow action.

• B-force (curl/flat)
• M-Lever (hook)
• W-Spill (hook)
• BS-Lever (curl/flat)

So as action flows strong, the Buck cuts off the perimeter as the force player. The Lever player maintains outside leverage on the lead back (attacking outside-in), engaging with the inside arm. The Spill player attacks the lead back inside-out. This forces either of these players free to attack the ball carrier and/or force the ball carrier to bounce to the force player or the backside lever player this puts the defense at a numbers advantage at the point of attack.

Dropping the safety, creates an 8 man front, and obviously puts the secondary in a 1-high (MOFC) coverage that essentially amounts to cover 3.

Even with the man principle (Vegas) the Lever-Spill-Lever concept remains with 1-high (man-free) man coverage, with a 3-on-2 on the backs with the M,W, and down safety.

With the tight end number advantage neutralized, and the run-fit supported within the front, how can an offense gain a strategic advantage?

If the front is set (by the tight end), the easiest thing an offense can do is move the tight end and reset the strength of the formation (trade). Bingo! Now, the offense has moved away from the teeth of the defense and has reset against the defense's deficiency.

With each Under concept (play) introduced, Pelini also introduces its front compliment (opposite). If the TE motions or shifts, the Buck linebacker will adjust. If teams attempt to Y-trade (shift the TE after the front is set), the defense already has a built-in answer. Because there is already an automatic response to TE trades/shifts, the advantage for offenses has been neutralized. This effectively eliminates matchup exploitations and offense could typically use before a game has begun.

If more than one player shifts, the defense will simply reset the front (see example below). Notice the DT and NT adjusting their alignment ('1' to a '3').


With the Over front, the same principles apply, with the exception of the Buck linebacker making the adjustment (away from the TE) and shifting the front (1 & 3 tech).




The Lever-Spill-Lever concept still applies to the Over front, simply by adding a down safety (away from the Buck linebacker) into the 7-man front.

As you’ll see in this example, Virginia tech comes out in slot to the field (walking the Buck out on the slot) and attempts to set the front with a tight end and upback to the field (quads). You can see the linebackers attempting to set an Over front (and looking at the front like, “you can’t be serious – who are you fooling with this quads set?”). Tech quickly shifts (aha!) to outflank the defense, only to have the linebackers simply reset the front with little thought required.





The corner assumes the boundary role to the closed side and acts as the force player (with the SS as help over the top).

The flow action has the corner establishing leverage to cut-off the perimeter and the Will (#52) fast-flows to leverage the runner as the ‘lever’ player. The Mike (#51) slow plays the action to squeeze the runner inside-out as the spill player.


The ball carrier is left with no legitimate options to find daylight (bounced to boundary corner or trapped by the spill / backside lever player). The backside Buck (#42) enters the play in a controlled lever position.



In subsequent posts, we'll take a look at how, out of these base concepts, Pelini routinely generates pressure through personnel groupings and coverage to frustrate and stall offenses.

Nick Saban: Leadership, The Process, and Cover 3

Nick Saban speaking at the Mississippi Association of Coaches Clinic yesterday.

( click for audio )

A great lecture sharing his philosophy on program building, dealing with athletes today, then follows up with him going over how he adjusts/morphs Cover 3 to handle everything an offense can dish out. 72 minutes of Saban.....................
Coaching is teaching
Teaching is the ability to inspire learning

Influence
Thoughts, habits, priorities - these are the triggers of everyone's actions

Develop Leaders
Leadership is understanding how what you do affects others

Rip/Liz (Rita/Lucy) linebacker adjustment in Cover 3
(though not articulated clear in MSU 97 or LSU 01 playbooks, I go over this 'safety-down' adjustment in cover 3 to handle verticals here)

more details on Rip/Liz here

Ball Security Drills

Ball Security is Job Security!

Thanks to the guys from Hudl who helped me to figure out how to do these presentations with video. You can do some cool stuff with the Presentation feature in using video to teach your players. Here is some of our practice footage from this spring. Ball Security is a big priority, and when pressed for time, you can work it while you are doing something else, such as quick feet drills or during dynamic warm-up. Just give your guys a football and make sure they are maintaining proper Ball Security at the same time. That way you can kill two stones with one bird (sic). This is one way we start off our Offensive Indy time for our skill guys:





Here is the link to the Hudl tutorial on creating a Presentation.

Trends: Zone Read

As I've stated many times, part of the satisfaction of watching football is experiencing the maturation of the game. With the Zone Read run game, the natural evolution to zone/stretch with bootleg compliment, the efficiency in creating a horizontal stretch of the defense is too productive to ignore.

NCAA_zone read @ Yahoo! Video

Will it 'catch on' in the NFL? Who knows, but judging by these clips below, it isn't going away any time soon, nor should it be regarded as just a "gimmick". This may also fundamentally change the way the professional quarterback (prototype) is viewed, or at the very least affect the way in which front office allocate personnel (bringing in multi-dimensional run/pass threat players).

NFL_zone read @ Yahoo! Video
NFL_zone read @ Yahoo! Video

Now, defenses must account for the 5 receiving threat +1. This in turn will force defenses to adjust/adapt either through personnel, fronts, or coverages (leading to a proliferation of nickel and dime packages).

Do you zone up and risk being overloaded by numbers, or do you man up and.......

NFL_special @ Yahoo! Video

...have no one account for the 'quarterback'.

Defensive Line (2001 Chicago Bears)

A little blast from the past here - the dynamic pairing of Keith Traylor (3 tech) and Ted Washington (1 tech) at Chicago.

While I'm not a big advocate of employing two bulky monsters inside (to essentially control B-to_B gap with just 2 defenders) simply because of the scarcity of athlete (not practical), this pairing was phenomenal in controlling the line of scrimmage. The following clips will illustrate how these guys were so successful in being disruptive in the run game; fundamental technique against various blocks.

If time permits, I'll add an addendum including clips of the 2000 Ravens with Sam Adams and Tony Siragusa.

Spacing...The Final Frontier - part 3

Here is Spacing on the backside of two-man Scat, which the Saints run a good bit in the cut-ups I have seen. Both are good 1 Hi concepts, which is what the Bucs Defense is in here. Scat can be deadly vs. Man in that it has an option for the RB to wheel up if the LB is chasing him. Scat takes a little bit longer than the regular Quick game concepts, so it is technically a five-step concept. Brees takes a quick three-step drop from the Gun. He sees that his frontside concept is not there, so he hitches up and begins his Spacing progression: Sit to Mini-Curl to Flat route. The Sit route is covered, but the Mini-Curl is open and Brees shows his precision by putting the ball to the side away from the defender maximize YAC (yards after catch).

Spacing (to Mini-Curl) @ Yahoo! Video

Pass Protection

The Pass Protection is a six man protection: half-man, half-slide with the FB check-releasing the two LB/DBs in the box to his side. This would be called 60 protection (60 = to the Right, 61 would be to the Left). 60 Protection is to the Right, so the covered/uncovered rules would start from the Right and go to the Left. The RT is covered and the RG is covered because both have a man head up or outside of them. They are the "Man" side and they will block the defender covering them. The Center is the first Uncovered lineman and he starts the Slide to the Left. The Center, LG, and the LT all slide backside--one gap to the Left. The LG will help out the Center with the 1 technique NT until a LB causes him to come off that block.

The FB check-releases by reading 1 to 2, from inside-out. If both 1 and 2 blitz, he will block #1, who would be the most dangerous. Also, if both 1 and 2 blitz, #2 would be an unblocked defender that the QB is responsible for. If 1 and 2 are coming from depth (blitzing from LB depth), the QB should be fine. If both 1 and 2 walk up on the LOS (line of scrimmage), then the QB or Center might need to change the protection.

There are also two LBs to the left of the Center. The Saints have 3 OL vs. 2 DL to the left, so one of the OL will be able to pick up one of the LBs should they blitz. If both LBs blitz, the OL is responsible for the most dangerous LB (the one nearest to the QB) and the QB is responsible for the other LB. The QB will have to get rid of the ball before the unblocked rusher gets there.

60 Protection @ Yahoo! Video

We will conclude the Spacing series with part 4 being the final read in the Spacing progression: the Flat route. Click on the Spacing tag below to see the previous Spacing posts.