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Purdue Football: Brohmfence 101 - Boundary Slant

Football is almost here, let’s look at some film!

NCAA Football: Music City Bowl-Purdue at Tennessee Steve Roberts-USA TODAY Sports

Here in Athens, Georgia, the crabgrass is knee high, 3 shower days are the norm, and traffic is snarled with 18-21 year olds returning en masse to campus. By my calculations, that means we’re about a month away from college football.

I’m going to be honest y’all, I get tired of talking about recruiting. Some people love it, but trying to read the minds of 17 year old high school students isn’t my bag. I do, however, enjoy college football, so let’s talk about actual football.

Film breakdowns tend to be my most popular articles, so let’s breakdown some film!

*I want to remind everyone that I’m an amateur at this. I also try and break these plays down in a way that everyone can understand. I try to stay away from football jargon because that’s not something everyone understands. If I’m not using the newest football lingo, please forgive my transgressions.

Boundary Slant

This play is a football staple. You’ll find a version of it in every playbook in the nation. Jeff/Brian Brohm runs a few different versions of the slant, but I like this one the best.

*I’m breaking my own rule a little. Boundary and Field is football jargon. “Boundary” is the short side of the field. In this case the ball is on the left hash, making Broc Thompson the boundary receiver. The “field” is the wide side of the field.




Red Box - Running Back/Slot Receiver- Danny Anthrop

Yellow Box - Running Back - King Dorue

Blue Box - Boundary Receiver - Broc Thompson


Blue Circle - Boundary Corner

Green Circle - Weak Side Linebacker

Orange Circle - Boundary Safety

Black Circle - Field Safety

Purdue initially lines up in shotgun with 21 personnel (2 running backs and 1 tight end). The backs are split to either side of the quarterback (red and yellow box). They have a wide receiver to the boundary (blue box) and a wide receiver to the field side. The tight end is flexed off the line.

Tennessee lines up in a 4-2-5 on defense. The key players for Purdue on this play are the weak side linebacker (green circle), the boundary corner (blue circle), the boundary safety (orange circle) and the field safety (black circle). No one else matters on this play.


Brohm uses pre-snap motion to give the quarterback (in this case O’Connell) an idea about what defense he’s facing (man vs zone) and to move defenders out of the space he wants to attack. You’ll see Purdue utilize motion on the majority of plays. When Purdue motions, and you see the quarterback check out of the play, it’s because the motion gave Brohm a new piece of information.

The goal is to open up a window for the boundary slant to Thompson. In order to do that, Purdue uses motion to the field side. Danny Anthrop (red box) starts in the backfield and then motions out to the field side slot. This is something you’ll see Tyrone Tracey do this season, and why Brohm likes the idea of having a RB/WR on the roster. It allows him to use the running back / wide receiver in the backfield as the motion man, instead of always putting a wide receiver in motion. It’s an added wrinkle for the defense to contend with, and Brohm loves overloading the defense with information.

When the running back (red box) motions out to the field side, the field side safety (black circle) steps up. That’s an indication to O’Connell that he’s looking at man coverage. If the safety doesn’t move, that usually means the defense is in zone, and O’Connell checks out of play (the quick throw to the slot is usually available). Since UT is in man, and the field side safety is responsible for the slot, the boundary safety (orange circle) has to drop off and cover deep. Tennessee is not going to play Purdue without a deep safety, because they know O’Connell can beat them deep (he already has once in this game already).

The boundary corner (blue circle) is in press man, and the weak side linebacker (green box) is milling around the line of scrimmage threatening to blitz.

Post Motion

Once the running back/wide receiver(red box) comes set, O’Connell has a good idea about what defense he is looking at, and where the players he needs to account for are lined up. The field safety (black circle) is locked in with the motion man. The boundary safety (orange circle) is bailing deep.

The main concern for O’Connell at this point is the weak side linebacker (green circle). He looks like he’s blitzing, but you’ll see linebackers bail out of that look at the snap and drop into the underneath boundary zone. That’s not ideal for this play. If O’Connell throws a pick on this play, it’s because the linebacker bailed and the slant hit him in the numbers. He has to account for the weak side linebacker.

Field Side Play Action

Brohm wants to suck the weak side linebacker (green circle) down the line of scrimmage and away from the throw. He utilizes play action to the remaining running back (yellow box) to move the linebacker.

O’Connell is looking to attack somewhere in the black rectangle. If you look back at the first picture, you see congestion in that area. Now it’s wide open. One other thing O’Connell needs to keep an eye on is the deep safety (behind the orange circle). When you see a wide receiver get smoked on this pass, it’ because the safety starts deep and immediately crashes down on the snap.

Everything looks good for the slant at the snap. It’s the boundary receiver’s (blue box) job to cut across the face of the boundary corner (blue circle), seal him, to give the quarterback and easy throw. The wide receiver has to win at the snap, and can’t let the corner get inside.

Perfect Execution

Everything works to perfection. The weak side linebacker (green circle) bites hard on the play action (yellow box). O’Connell knows he’s got the window he needs to throw the slant to boundary receiver (blue box). Now it’s up to the receiver to beat the boundary corner (blue circle) inside. You can’t see this but the receiver (Broc Thompson) set the corner up with a hard step outside to push him toward the sideline and then broke inside across his face. The deep safety (behind the orange circle) is still deep, and isn’t a factor.

This is exactly how this play is supposed to work.

WR Wins

Broc Thompson (wide receiver, blue box) gets across the face of the boundary corner (blue circle). The weak side linebacker (green circle) realizes it’s play action, but is too far down the line to get back into the throwing window. The deep safety (orange circle) is still deep. He’s not a factor in the play. Thompson isn’t going to have to worry about getting his head knocked off. This is a simple pitch at catch.

O’Connell delivers a catchable ball and Thompson (blue box) has the corner (blue circle) sealed on his backside. The deep safety (orange circle) is pulling crabgrass somewhere around the 30 yard line.

All that’s left is the catch.

Solid Gain

Thompson makes the catch, and drags the defender for a few extra yards. The deep safety (orange circle) is defending his piece of turf 8 yards away from the play.

In Conclusion

I’m showing you this play because it’s a good illustration of how complex college football is, even when it looks simple. When you’re watching at home in real time, all you see is O’Connell hit Thompson on the slant for an 8 yard gain. It’s hard to appreciate all of the little things that went into getting him open. This is why execution and attention to detail is critical for Purdue’s passing game. It’s also one of the reasons why I’m optimistic about Purdue’s offense this season.

O’Connell has full control of the offense, and the play book is wide open. Instead of slogging through another install with a new quarterback, the coaching staff is able to focus on execution in fall camp. I expect that to play huge dividends over the course of the season.