For the next few weeks, we’re going to look at basic defensive coverage schemes and how the Buffalo Bills have used them. These will be 101-level introductions that just begin to hint at the schematic complexity NFL defenses employ against the best offenses in the league, but they’ll give you a leg up in trying to understand why a defensive back was in a particular part of the field or why that linebacker ended up covering a wide receiver.
Our second coverage scheme is Cover 2. We’ll break it down below, but let’s start with how the Bills utilize it.
According to Sports Info Solutions, the Bills used Cover 2 against 100 pass attempts, which ranked fourth in number of attempts. The Bills’ defensive statistics (and ranks) when using Cover 1 against pass attempts are pictured below. This number from SIS may differ from what you might find elsewhere because it’s based on whether or not there was a pass attempt. For instance, if the offense used a running play while the Bills had set up in Cover 2, it would not show up here. Either way, the Bills ranked high in how often they ran Cover 2.
Unlike Cover 1, Cover 2 is a zone scheme. The name comes from the safeties’ alignment, with each safety deep and responsible for a deep half of the field.
This chart is a derivation of one done by Glover Quinn, former Lions’ safety, in his YouTube series The DB Room. You might see other Cover 2 charts that describe the inside routes within the 5-10 yard mark (purple) a little differently because there can be some variability in how they are defined. There are versions with only three middle under zones delineated. There are versions where Hook and Curl are lumped into the same box. The bottom-line takeaway is that the field is divided into sections, and each defender who isn’t one of the four linemen has a coverage responsibility related to those zones.
Cover 2 Responsibilities
Safeties – Each safety will start 15-20 yards downfield from the line of scrimmage, a couple of yards in from the numbers. Their job is to pick up any receivers on deep, explosive play-type routes. Each safety has to keep the play in front of them for as long as possible. They need to see the routes develop, and they want to cheat a little based on the QB’s eyes. At the snap, they’ll start with a backpedal, but they don’t want to get too wide too soon and leave the middle open to a post route, which starts wide and then angles toward the goalposts, eventually coming toward that seam between the safeties. Each S is trying to cover a little more than 26 yards in field width, so the system is designed to make their life easier, and that starts with the outside CBs.
Cornerbacks – For Cover 2, each outside CB plays high to low and starts with a Jam/Funnel/Sink. Typically, CBs will be in press position at the snap, because their first job is to jam the receiver as he comes off the line. Try to disrupt the timing of the play for the offense by forcing the receiver to take extra steps or not quite hit his mark on the route. The jam should coordinate with the leverage the CB plays to. Using outside leverage is meant to funnel the receiver toward the middle of the field so, ideally, the S doesn’t have to worry about the “honey hole,” that area outside the numbers 15+ yards downfield. If the cornerbacks can help shrink the width of the field for the safeties, their job becomes significantly easier. Routes that stay under 15 yards are funneled to the linebackers or nickel defender. Next, the CB must sink to help cover the out zone. If the receiver is running a post-corner or option route, it may look like he’s been properly funneled, only for him to break back to honey hole. By sinking, the CB at least forces the QB to have to throw over his head. If the pass goes under him to the flat, the CB needs to quickly come up from their sunk position and tackle.
Linebackers – For the Bills, who play 90%+ nickel, this also means Taron Johnson. These under defenders are watching the QB’s eyes, dropping slightly in a backpedal, looking to disrupt timing, and trying to funnel the number two receiver on their side. For the defense, receivers are numbered from the outside of the field on both sides. In our diagram, the X is the No. 1 on the left and the Y is the No. 2. From the right, Z=1 and S=2. The weakside LB and NC are looking to funnel those number two receivers while paying attention to how the outside cornerbacks are reacting to the ones.These players also can’t go chasing receivers into the out zone and leave the middle of the field wide open.
The middle linebacker starts with reading the center and guards for pass vs run distinction. If it’s a pass, the Mike drops like the weakside LB and the NC in this standard version of Cover 2. In the well-known Tampa 2 system, the Mike needs to drop back 10-15 yards and help cover the deep middle. Think Brian Urlacher.
Defensive Line: With seven defenders in coverage, there is only a four-man rush. The DL has to be able to create some pressure with just these four linemen.
If you haven’t seen it already, communication for the back seven defenders is critical. They have to work as a unit and pass receivers through the zones, through different responsibilities for different defenders, and still maintain the integrity of the scheme. Plus, it’s a vastly different skill set from man to man. Instead of just locking onto a pass catcher and trying to stay in his hip for the route, defenders need to position themselves to see more of the field so they can anticipate, react, and close with violent quickness.
Man Under presents just like Cover 2, and the safeties still each have responsibility for a deep half. The difference from standard Cover 2 is that the other defenders covering those shallow routes – the under routes – are in man-to-man. In an oversimplified form, this is a disguised coverage: it presents as Cover 2 at the snap but operates differently post-snap, leaving the offense to react. Not that Man Under is stronger or weaker than Cover 2, but that the change from pre-snap look to post-snap reality forces the offense to adapt on the fly.
Basic Cover 2 is a relatively simple scheme that acts as a foundation for a lot of the more complicated coverages. When we get to Cover 4 and 6, we’ll see how they build off this elemental system.
Next week, Cover 3.