The response to last week's quick and dirty look at Kentucky's base 4-2-5 defense was positive enough that we'll "open the playbook" a little bit more and take a basic look at defensive coverages. While reading, remember that defensive coverages aren't sacrosanct (i.e. there's no such thing as "we only play press man coverage"), and are usually determined by an offense's personnel, tendencies, and formation. Teams at the collegiate and professional levels run multiple coverages at different times to create advantages.
Rather than reinvent the wheel there will a heavy reliance on other SB Nation blogs who have already done most of the work. Before we get to the X's and O's, though, I thought it may be useful to read how Mark Stoops' brother, Mike Stoops, describes the defense he and oldest brother Bob Stoops run at Oklahoma, specifically the coverages, because it is similar to what UK ran last season:
4-3 over is our basic call versus any two-back run team. This call will allow our strong safety to be our low safety or eighth man in the box. He is responsible for the B-gap on the inside run game. Behind this call, we will play a three-deep zone coverage. You can also play a man-free concept putting the strong safety on the tight end if he runs vertical or over the linebackers. Sam will drop curl/flat, Mike will drop strong hook and Will will drop weak flat. The free safety will push to the middle of the field. Versus twins or slot formations, we will bring our corners over and play three-deep or man free.
The strong safety is six or seven yards deep, head up on the tight end. The free safety is 10 yards deep where a tight end would be. If on the hash, he will line up over the tackle.
The strong safety will key the tight end. When the tight end base blocks, the strong safety will go straight for the B gap on lead strong. The Mike will spill the ball to the strong safety. The Will takes the back side A gap. On lead weak the Will has to spill the ball to Mike who fast flows. The strong safety will take B gap.
Here Mike Stoops is explaining how he likes to play "a three-deep zone coverage (Cover 3)", and a "man-free" coverage (Cover 1) against teams with two backs. In offensive formations with two backs, and generally three receivers, these are the two coverages he will generally play. This typically resembles UK's approach last season too.
Note: The following illustrations were provided by SB Nation sister blog Coug Center.
The zone coverages illustrated below (non Cover 0 and Cover 1) are based out of the 4-3. UK will still align in the base 4-3 this season, but will also align in the 4-2-5 and even the 3-4 base defense at times. As a general rule just substitute out the "S" linebacker for the nickel back and you'll have the 4-2-5. Finally, not only will UK's defense be multiple but its coverages will be too. For example, UK is set up to transition between coverages easily with five defensive backs on the field.
This is man coverage with every member of the secondary matched up with an offensive skill position. This is rarely seen outside of short yardage situations due to big play vulnerability. Teams with superior athletes can get away with it at times, but it's still a gamble. UK did not show this outside of the goal-line or short yardage last season if I recall correctly. They probably won't in the future either as it seemingly goes against Stoops' defensive philosophy.
Cover 1 is the "man-free" concept referenced above. It is a variation of man coverage but with the free safety playing deep, and acting as a last line of defense. He is usually roaming along the middle third of the field, reading the quarterback's eyes, and looking to help any of his co-defenders who have gotten beat or being challenged. UK showed this look against Mississippi State last season (image #2 gives the best angle).
Cover 2 gets its name because the back part of the secondary gets divided into halves. This is the first defense many kids learn to run at the elementary and middle school levels, and some carry on into high school. A variation of this coverage is the Tampa 2 defense popularized by Monte Kiffin and Tony Dungy in the NFL.
Along with Cover 1, Cover 3 appeared to be the most common coverage last season for UK. It gets its name because the back part is divided into thirds. Unlike the illustration, UK tends to have two safeties deep pre-snap instead of just one. The nickel back would take the position of the strong safety (SS) and the SAM linebacker (S) would disappear.
UK can be more varied in which three deep zones gets filled by which member of the secondary too. Maybe its one safety and two cornerbacks. Maybe its both safeties and one cornerback. You get the general idea. Nick Saban refers to these wrinkles as "Sky" and "Cloud" (more in the reading list below). This coverage, like the others, can become more advanced.
Cover 4, or "quarters", has the defensive backs filling four deep zones. This coverage has risen in popularity to counter the spread in the last five years or so. Pre-snap looks like Cover 2 if one only looks at the safeties. Instead of back pedaling at the snap, like they would in Cover 2, the safeties remain still and read the offense. This gets more men in the box, while leaving time to get four defenders back deep in case it's a pass play. If four receivers go deep then this coverage basically turns into man coverage back deep. Unfortunately, the outside linebackers are expected to cover a lot of ground. Adding a nickel back gets more speed on the field though. Stoops ran Cover 4 while at Arizona to slow down Oregon's HUNH, spread offense. While Arizona lost in overtime, his tactical decision gives at least some insight into his counter-spread views.
This combines Cover 2 on one half of the field with Cover 4 on the other half. Defenses typically run this coverage if they want to add an extra defender to the side where an offense has a great receiver, or if one side is overloaded with receivers (like a trips set). It can also deceive quarterbacks into throwing into double coverage more often than some of the other coverages. UK appeared to at least run this coverage at times against UofL's Devante Parker, Vandy's Jordan Matthews, and against Mizzou's trips formations.
It's not always easy while watching games to see what coverage the defense is running. Games that air on television typically focus on the line of scrimmage, and go on to follow the ball from there. Sometimes it takes multiple rewinds, and highlight replays to try and piece together a complete picture. Even then you still have knowledge gaps. Here are a few basic tips to help diagnose the defensive coverage from your recliner (hint: watch the cornerbacks):
- Cornerbacks lined up close to a receiver typically indicates man coverage (Covers 0 or 1).
- Cornerbacks five yards or more off a receiver typically indicates zone coverage (Covers 2, 3 or 4).
- Corners tight, two safeties deep starting on their hashes, and outside linebackers "splitting the distance" between the inside receiver and the last man on the offensive line on their side (offensive tackle or tight end) typically indicates Cover 2.
- A cornerback five yards or more off an outside receiver with a nickel back less than five yards off an inside receiver on the same side of the field could indicate the nickel back has the shallow zone while the cornerback has the deeper zone on their shared side of the field. This could be a Cover 3, Cover 4, QQH coverage.
- Watch how the linebackers react after they read pass, and notice which zones do they head to, or what offensive player do they match up with man to man.
Still Want To Know More At This Point?
Browsing around SB Nation I came across a few posts that go into more details regarding defensive coverages. These provide more in-depth information.
- Understanding coverages.
- Cover 3 specifics, details, and variations.
- More on Auburn's 4-2-5 and "Robber" coverage covered last week.
- How Virginia Tech adapted to spread offenses schematically.
- Cover 4 against the spread.
- Cover 2 specifics, details, and variations.
- Saban scheming against Johnny Manziel.
If interested in specific Mark Stoops views on secondary fundamentals and their reads, I'd recommend an old coaching tape of his days at Miami. He talks a lot about defensive back fundamentals, but he also makes plenty references to wider scheme and philosophy.