This article is partly about the curl-flat concept and partly about how to run the same concept out of many formations, making it appear to be different plays just by changing the formation.

It was good enough to fool me. Originally, when I was studying the North Texas offense, I had it written down as Curl-Flat, Snag-Flat, and Hitch-Swing. I treated each play as a brand-new concept. After a few weeks of deep diving into their offense, I recognized the connection. It’s the same concept but out of different formations. This is where Coach Neal Brown from North Texas is an offensive genius. He changes where his chess pieces are lined up but doesn’t make them throwaway pawns. He uses the new formation to make the concept even better. This is the lesson that can take your offense from good to REAL good.

If you haven’t watched my YouTube breakdowns of the North Texas run game, those videos will help you get a feel for how their split zone action works. Here’s the link so you have access to it.

North Texas Run Game Breakdown

North Texas runs three base runs, all off split zone action, so it only makes sense to run curl-flat off split zone action. Everyone runs play-action off their base run.

When they’re in their H-back sets, they run curl-flat as a play-action pass. With the H-back in the formation, we’re telling them we might be running outside zone, one of our premier run plays. So, we fake the outside zone with split zone action. The H-back cuts across the formation, and everyone blocks it just like outside zone, which gets the middle linebackers to bite. With the middle linebackers preoccupied, it makes for an easy read on the outside linebacker. If he covers the curl, hit the flat. If the OLB runs to the flat, the curl’s wide open behind him. So, we have our first formation. When we’re in H-back sets, we know curl-flat means fake outside zone for everyone, and we’re running curl-flat to the two-WR side. Simple.

Now we’re going to run curl-flat out of a TRIPS formation. This is an issue because we throw curl-flat to the two-WR side when we have an H-back. So, North Texas has an easy solution. Use the back as your second WR. Instead of curl-flat, it will be the same concept but with a curl and an RB swing route as the flat threat. This keeps the read exactly the same for the QB. North Texas tags the three-WR side with whatever concept they want. I’ve seen SMASH with the #3 also on a hitch. I’ve also seen a LEVELS concept, but honestly, the QB never throws to the trips side when curl-flat is called. Now we have our second formation. When we run curl-flat out of trips, I’ll tag the trips side, and curl-flat will be run by our isolated WR and the back out of the backfield. Same read for the QB. Simple.

Now for the third variation: curl-flat out of 2x2. We are back to our two-WR side. Perfect. We can run our normal curl-flat to the two-WR side, but it’s hard to sell our split zone play-action because we don’t have the H-back in the formation. We wouldn’t be fooling the defense. So, instead of inventing a play-action pass off a run play we don’t run, we just run curl-flat out of 2x2 as quick game. We don’t have to pass protect for very long, so our six-man protections are good against most 2x2 pressures, and the ball’s out quick. Works perfectly.

Here is where I get impressed with Neal Brown’s whiteboard skills. He knows he gains an extra WR in the curl-flat concept with the inside #2 away from the call side. Well, why not utilize him in the concept, just in case it’s covered? The #2 away from the call side runs an over-the-ball curl, similar to the OTB we see when teams run mesh. Neal Brown is very familiar with Coach Mike Leach’s All Curl concept, and I think this is just a modern variation of it. So, now we essentially have a double curl-flat concept. Out of 2x2, when we run the curl-flat concept, the #2 away from the call side runs the OTB route. Understood? Simple.

We now have three ways to run curl-flat, all out of completely different looks. The real kicker is we’ll line up in one formation and motion to another. We’ll line up in trips and motion to 2x2, then run our 2x2 curl-flat—quick game with #2 running the OTB. Or we’ll start in 2x2, motion a slot into the H-back position, and run curl-flat as outside zone play-action. If we know how the concept is run out of that formation, it makes it so easy to see the adjustment.

I hope this article helps you understand how an advanced offense keeps it simple. Three formations, the same concept with just a few subtle tweaks. Can you envision any formations and plays that could have a similar tweak? I hope this helps.

Adam MaCauley is the face behind Simple Football Systems. If you’d like to read and watch more of Adam’s content subscribe to his YouTube page by clicking here.

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