Overview of Zone Blocking

Bumped. GO BRUINS. -N

I'm going to explain the zone blocking scheme that is probably one of the most common, if not the most common, run blocking scheme in football today. Zone blocking is nothing new and there are countless articles and videos floating around the internet and in football broadcasts that have given great explanations, so much of this will probably be familiar to those of you who watch a lot of TV. I will attempt to give a general overview of zone principles as well as some general keys to defending them. Next time I want to take a look at specifics of the zone play in the Pac-10, especially the Oregon run game as it was requested by another poster, and responses to the ways teams have used this concept. But before that, I would just like to give the big picture of what zone blocking entails and why teams have moved to this concept in the run game.

The basic premise behind zone blocking is that every blocker is responsible for a gap rather than a man - its the same principle behind zone pass protection. In a nutshell, each offensive lineman has to block the man who threatens his playside gap. I'll get into more detail into how this works below the jump. To get an idea of what this looks like in practice, here is an example of an outside zone play being run by the Texans against the Colts from a few years back. If you are watching a game on TV and you see the whole OL step one way on a run play like in the video, then it's probably a zone play. Watch how they all step to the left and try to "reach" the defenders to wall them off from the back. 

Notice that the DE and DT to the left both slant back inside. The TE arc releases downfield to block the safety (the FB is probably assigned to block the first LB). LT #74's first responsibility is to block the man threatening his playside gap, the DE over the TE. Since he slants across his face backside, he passes him off to the next guy, LG #69, and climbs to LB level. The LG would originally block the DT since he is shaded in his gap, but that DT slants inside as well and so he passes him off to the center. The center has no one in his playside gap but sees the DT slanting in and picks him up. On the backside, the RG blocks the guy in his gap, and the RT has no one so climbs to LB level. Notice the DE all the way to the right is unblocked and runs laterally down the LOS and almost makes the tackle. If you've watched any college football over the past few years you probably know how offenses have dealt with this guy but I'll get into him later on.

Below are the blocks on paper (left) and how they actually played out (right). I'm not sure how the Texans would have played a 6 tech DE that did not slant. It looks like to me that the TE was set to arc release no matter what. Either way the offense would probably try to kick him out towards the sidelines since it is impossible to reach him with either the LT or the FB. You can see the OL still take their first steps to the same area even though they ultimately end up blocking different defenders depending on how the defense moves at the snap.

Below I'll be talking about 1) inside and outside zone differences, 2) blocking rules in detail and some general coaching points, and 3) how to stop it.

Inside and Outside Zone (IZ/OZ)

The names are fairly descriptive of what these two plays are trying to accomplish. Inside zone is looking from hole to cutback; linemen are looking to drive their defenders north-south or wall them off outside to make a crease for the back. If the defense over-pursues and leaves a crease backside the back should take it. Outside zone is looking from hole to bounce outside and the line is looking to take a wider step at the snap to secure outside leverage on the defender. The offense is looking to pin everyone back inside and create a lane outside for the back. However if a player stunts wide outside and wants to go there, a lineman can keep driving him towards the sidelines as long as he is out of the way - the goal's just to rely on lateral movement and leverage rather than brute force.

These two plays complement each other. A team can base off of inside zone until the defense tries to cheat inside and then they can run outside zone, pin the defense inside and bust a long run down the sideline. However, they are usually taught together since they are very similar. The basic difference from a teaching standpoint is the footwork for the quarterback, back, and linemen. Once the OL understands zone rules it is not difficult to teach the outside zone.

Blocking Rules

It takes a lot of time and practice to teach the blocking rules for zone. Linemen need to understand what they are supposed to do and how they should react to stunting linemen. Once you understand how to block zone and have practiced it over and over, it is very adaptable to various fronts and you don't need to spend time on it later. It eliminates complicated blocking rules for each position and for each specific front. For the most part the entire OL has the same blocking rules and is looking at the same keys depending on whether they are covered or uncovered by a defensive lineman.

However, it is a system that you need to "marry" - you won't see the full benefits if you just "date" it because it takes a lot of reps to get down. I can't think of any team that only runs zone once or twice a game - teams that run it (which is almost everyone) generally rely on it for about half of the run game, if not more. Fortunately it has become very commonplace at every level of football so I don't think that any NCAA program has to worry too much about recruits who have not encountered it in some form or another. However, each team may have their little wrinkles about blocking rules and footwork and it is important that everyone is on the same page.

Most teams use a "covered/uncovered" rule to determine combo blocks. If an OL is "covered" (has a DL on or shaded to either side of him) then he is looking to form a combo block on that guy to LB level. If an OL is "uncovered" then he is looking to help out playside to the covered lineman next to him.

In this diagram the ball is going right. LT, C, RT, and TE are all covered. Both guards are uncovered and are looking to combo block with the OL to their right. Who they actually end up blocking depends on what the defense does. Remember, each OL is responsible for their gap, not a man. On paper, the TE will make a solo call on the LB lined up over him. RT will contact the DT and then make his way up to the LB. According to his they are aligned right now, the DT is not in the RT's gap so he will pass him off to the RG. RG will take a lateral step and aim for the DT's inside number. Hopefully the RT has helped out and pushed this defender towards RG. C will block the NT since he is in his gap. LG will combo NT to the LB. LT is covered and will take the DT. These are the blocks on paper, but on practice things get more complicated as the defense starts to move around.

"But coach, what do I do if the DL slants backside?"

OL should be passing guys who slant backside to the backside OL - they are responsible for their playside gap. If NT above slants backside across the C's face, he gives him a shove and works up to the MLB. In any sound defense, if a player slants, then another player is going to be responsible for their gap. If NT slants backside, MLB is probably responsible for his original gap. Linemen cannot chase defenders and must be able to react to stunts instantly - if the player goes elsewhere then someone else is probably coming to you.

"What if I'm climbing to LB level and he runs backside?"

Same deal. Find work.

"What if we are running OZ and I can't get outside leverage on my defender?"

Take him where he wants to go. Zone just requires moving the defender laterally away from his gap. If you are the end man on the line and there is a DL shaded to your playside shoulder, and he steps outside and is fighting hard to hold the edge - rather than trying to reach his outside to block him back inside, you can just use that momentum to keep driving him towards the sidelines. Either way he goes, he is still going to be out of the way. You don't need to be able to power guys off the line and drive them backwards (although that helps), you just need to understand leverage and use lateral movement to block people.

"How long should I block a player shaded backside?"

If you are RT and have a guy lined up on your backside shoulder, you should first be wary of him slanting across your face. If so, he is now your man and the RG will need to look for a LB looping back or something. If not, you need to imagine that you're on a track, heading to the playside gap. If any arms or shoulders are on the track, you shove them backside to help out the next guy. If you don't have any contact with this DL on your track, then you assume he slanted backside on his own and the RG will be in good shape. If you don't make contact after three steps then you do not worry about a backside shaded defender. You just have to trust that your fellow lineman has picked him up.

Stopping Zone

There are several things that work well against zone. Here is the video that corresponds to the points below.

#1 is a defensive line that is able to control the LOS. You need to get movement to run zone. If you face a DL that is consistently in the backfield then you are going to struggle. If there is a weak link in the OL and the defense finds it, you will struggle. If defensive coaches notice that a certain OL has trouble sliding off the double team to pick up a LB, or is not quick enough to reach a playside shaded DL and is beat consistently, then you'll struggle. If the unblocked backside player is crashing down the line like in the first video clip, then you are going to have problems. He is going to be able to make some tackles from behind, and as an offense you need to find ways to deal with him if you cannot block him. In the video above, watch both of our DTs against ASU as they drive a few yards into the backfield to make the tackle. They establish a new LOS in the backfield and there is no gain on the play. As you can probably guess, the zone read is one of the ways to deal with this, and I'll go over that in detail next time.

#2 is defensive stunts. The zone works well against stunts as the OL are supposed to block a gap not a man, but when dealing with high school or college kids, your bulletproof schemes on paper are not always going to work on the field. In the video, watch #74 the RT for ASU in the second clip in the video above. He lunges at a DE who slants inside while Bosworth and Carter both scrape over top. The RT gets spun around and off balance and ends up blocking no one. There are 3 Bruins behind him in the backfield, as well as Reggie Carter who shoots into the gap. However, there is a flipside to this as you still need to maintain gap integrity when you start to get fancy or else the offense can hurt you.

#3 is fairly obvious. I didn't bother including that whole play (piggybacking off the second point) but Justin Nance gets about 15 in what should've been a 3-yard loss. He juked the entire Bruin defense on that play and made his way downfield. You need to not only tackle well but stay in your gap. If you bunch up then there will be a cutback lane somewhere and a good back will find it.

#4 is aggressive LBs scraping to the ball. Most linemen struggle in space against fast linebackers. A OL climbing to the second level to pick up a LB means nothing if the LB just runs by him. In addition, quick LBs that scrape over top into a gap force the OL to keep one eye on the LB and slide off to pick him up if he scrapes into the next gap. It is really easy to make blocks on paper, as I showed above. However, in practice, things are more difficult, and a defense that moves around is tough to block. It's tougher to pick up a LB scraping over top of a DL, especially when they align close to the LOS. In the final clip in the video above, Reggie Carter presses his gap aggressively and the RG is too slow to really block him. However, if your LBs fast flow, then you need to have some kind of backside pursuit behind them in case of a cutback. In that clip, there is no one behind Reggie Carter in case the back finds a crease back there. If you fast flow, you will need the backside force player to play cutback if you want to remain sound. Unfortunately, this will weaken your defense in other areas, and offenses today have capitalized on this.

Being physically dominant and tackling well/playing gap disciplined are two things that you should always try for. The other things - playing aggressively downhill to fast flow and stunting - are controlled by scheme. It's really easy to say that your defense needs to do that. However, it's not something that you can do all the time. If you crash the backside DE down every time to chase the ball from behind, offenses will hurt you. If you are fast flowing every time you read zone, offenses will hurt you. If you run stunts, and happen to guess wrong (in the first video, the Colts stunted two DL backside), offenses will hurt you. If you over-commit with alignment, they will simply check off and hurt you. You cannot do these things all the time, and you can't do the same thing every time, otherwise the offense will make you pay.

Next time I will show some of the ways Pac-10 teams have used the zone concepts outlined above in their offenses.