Waaaaay back in the nonconference portion of the season Michigan was getting repeatedly gashed by slants. The problem hit a crescendo against SMU, and their excellent little slot bug James Proche.
SMU threw six slants for 44 yards on 4 completions; only on the last did a safety make a play on the ball, and there’s a big reason for that we’ll get into further down. As the season’s progressed, however, Michigan’s gotten much better not just at defending slants but convincing opposing offenses not to even bother with them by running trap coverages. Why were we bad at them before? Is that a hole in our base defense? What’s a trap coverage? Let’s discuss.
Defending Slants and Fades with Man Coverage
The reason Michigan was bad at slants was they were bad/unlucky last year at fades, and made a conscious decision to be align in a way that made fades harder and slants easier.
Michigan likes to run a lot of Cover 1: man to man defense with single high safety. They also like to blitz their linebackers and play them aggressively against the run. The coverage has help inside on deep plays but no help outside, and small help underneath. Offenses learned long ago that you can put a Cover 1 slot defender in a bind by threatening him short/inside (a slant) and deep/outside (a fade). Both routes start by running directly at this guy, trying to get him to flip his hips to defend whichever of the two you’re not running.
[After the JUMP: a wild Mon Calamari appears]
Slot defenders expecting one or the other can “cheat” by alignment. It’s not equal: defending a fade means flipping around and running with a guy who doesn’t have to change direction, while on a slant it’s the defender who gets to break directly toward the ball while the receiver has to run twisted.
Of course you can align inside if a fade’s not a concern, such as in a goal line situation, e.g. the one successfully defended slant vs Cov1 in the SMU game. Look where Metellus lines up here:
#14 just below the bottom hash
That has been rare. On the slot-fade defense slider, Michigan went into this season with the bar set all the way to fade. The hope was their safeties were experienced and athletic enough to deter fades by alignment and still be able to drive on slants, at least enough to make slants a bad play. Against a serious man like Proche that was incorrect, to the tune of 8.8 yards per attempt when they tried it. SMU also threw four fades; one drew a ludicrous flag from the rent-a-refs, and one was a ludicrous catch that passed through a defender’s arms and was caught on Proche’s inside arm and hip (not exactly how they draw that up). All of them were far likelier to be intercepted than caught by a receiver, and SMU soon abandoned them rather than continue to try their luck. But that was Proche. How was the rest of the season going:
NEBRAKSA: Frost certainly wanted to try the slant but after SMU he didn’t trust Brown to keep his linebackers from dropping into them, so he added a Run-Pass Option. It’s here if you want to watch it but not really relevant because Nebraska was in an illegal formation (not called, because the John O’Neill crew is worse at their jobs than the MSU beat is at theirs) and the defense (as a player’s parent clarified to me later) decided the slot defender heading downfield wasn’t eligible.
NORTHWESTERN: This game was even more slanty than SMU. I clipped 14(!!!) plays on the drive back from Chicago that I thought a slant was the primary read. It was quite simply Northwestern’s gameplan to have Thorson throw slants, mostly at his slot receiver, and Michigan’s gameplan was to let them try. Note where Kinnel is lined up on this one relative to the slot receiver. Thorson threw the backside slant but Kinnel was beat more than Long:
…before Don Brown finally dropped his linebackers into specifically “F yo slant” zones.
Why Not Drop the Linebackers?
My theory of defense is there’s three ways to win a down:
- EXECUTE: Run a vanilla play that’s sound against most things and everybody executes.
- ROCK, PAPER, SCISSORS: Run a special—read: normally unsound—play that’s designed to beat the offense’s playcall, and
- DOMINATE: Have a guy make a great play despite starting in a disadvantageous position.
For Michigan’s base Cover 1 defense, dropping the linebackers into the alleys in this way is #2, i.e. Don Brown is throwing paper on Northwestern’s Rock. It’s unfortunate (or perhaps a last second minor course correction) that Thorson was so inaccurate on this ball because otherwise it’s picked. Ditto when Wisconsin came out with slants, Devin Bush batted it, and a Badger receiver caught it (though short of the 1st down):
This is certainly a response, especially on 3rd and long, but it’s untenable given how Michigan wants to play. A Don Brown defense wants to sell out against the run as much as possible. They don’t want linebackers dropping out of the middle all the time like weak-ass Buckeye OLBs. We want them jamming up running lanes, flying to ball, and threatening all kinds of blitzes. Sure, once in awhile they’re going to drop back, but the defense’s whole identity is Devin Bush looking hungrily at your rib cage.
To get that, Michigan had been asking their secondary to pull off #3, and running their base Cover 1 so much that opponents could expect it and gameplan for it—sitting on the fastball if you will. What Michigan really needs to shut down the slants is a two-seamer, a different OPTION 1: a hale defensive base strategy that still fits their philosophy.
What could that be?
…psst Ackbar, your cu—
Don Brown wonks have been looking for this since we first got our hands on his Boston College playbooks.
Another victim of that version of Powerpoint that treated lines as shaded objects
Brown's trap coverage moves the cornerbacks into the slots, covering any leaky outside receivers with the safeties reading outside-in. The squigglies mean the defender is shuffling to that spot, not running. The numbers refer to the receivers, counting from outside->in. Any eligible receiver who pops out a side gets added to the number, so if you've got #2 and the RB goes out in the flat, you've got the RB. In this coverage the safeties only have the #2 receivers if #1 is taken care of—until such time they're the OLBs' problems.
This was an oft-used defense for Boston College—the playbook even notes that "Eagle" is their base call when they get tempo'ed unless they've set a different call that week. But for Michigan it's been a rare pitch. I found one play I was pretty sure was trap coverage and one that used a trap trick for Michigan's base Cover 1 between Northwestern or SMU's slant-a-thons. But Michigan did break out the ol' trap against Wisconsin, and immediately got a pick from it.
That was a curl-out route, not a slant, but attacks the same spot as a slant, and the description in the video above is a pretty good one. I would add that the reason it's called a Trap is because you're baiting the quarterback to throw into this area by showing him a look that would suggest the cornerback is about to vacate the area, and then he doesn't.
Look at all the grass behind David Long where they've drawn a yellow teleprompter line. Look where the safety is playing: on top of the tight end. A quarterback who's played against Cover 2 and Quarters teams will reasonably conclude he's looking at a nice soft Cover 2 shell, and know that he's got a nice, safe throw into all that room underneath it. It's only after he releases the ball that he realizes the cornerback wasn't vacating the premises:
What do the cornerbacks have to do to earn such a coverage reprieve? Why, defend the run of course. Here's Zordich when he teased trap coverage in a 2016 preseason presser:
MGoQuestion: If we could talk trap for a little bit, how do you coach that for your guys? Is it brand new to them?
“I wouldn’t say it’s new to them. For them, it goes back to high school days when they were playing cover 2, when they were hard corners. Their read has got to be the end man on the line of scrimmage, so it’s really nothing new as far as they have to deal with. It’s just that it’s going to be more often than what they’re used to from I’d say a year ago.”
They're in the slot, and slot work is about being an edge run defender, especially in this defense that stops the run first. This can be a nice surprise against a team that likes to run out the sides and suddenly finds an edge setter already hanging out there like Lavert Hill in this example from the Penn State game last year:
#24 the cornerback at the bottom of the screen:
There are some other pieces to it so they can run it against any look without being unsound. The cornerback and safety are playing the coverage together and a cornerback may at times have to take the #1 WR (for example when two receivers are stacked). If the corner calls an "INVERT!" the safety takes that curl/flat zone and the corner backs into the deep job, reading 1 to 2.
I couldn't find a direct example of this but we saw something similar to an Invert on a couple of 2nd half slants vs Northwestern:
This is a Trap tweak to Michigan's normal Cover 1 but works the same as a trap, or should—Kinnel oversold his deep middle third and came up too late but the way this was drawn up should have been an interception.
Watch Metellus (2nd guy from the bottom) bail to a deep zone while Kinnel hammers down. It's a big hit that should by rights have jarred this ball loose, but the design was for Kinnel to dive in there in time for a pick:
They ran something that might have been a true trap invert in the 4th quarter. Watch how Hawkins (the high safety on the bottom of the screen) screams down:
Thorson by now has gotten wise to Michigan's attempts to mess with his slants so he rolls out and tries to find something on the other side, so we can watch the trap coverage develop over a longer play, with the CB (Watson) and S (Metellus) swapping guys as they twist, converting into a more normal Cover 2. Hudson didn't drop far enough and gave up the completion and that's an issue with this coverage: the OLBs become virtual safeties with deep dropback hash-to-the-numbers zones and a lot of ground to cover, and even the hybrid safety of the defense is not wholly comfortable with that.
Another tweak is to play the receiver outside off press man before showing the trap coverage. Michigan won't do that if the cornerback is the only defender between the last guy tight to the line and the sideline. Watch Long on the second Badgers trap:
#22 cornerback at the top of the screen
With no run threat out there the cornerback is free to start out more like those sticky match zones like MSU (Quarters) or Alabama (Pattern-Matching), with the corners up on the #1 receivers and everybody spending the first few seconds with the man they're lined up over.
At the snap it looks like Tampa 2, with the OLBs widening to "buzz" (cover over) a quick attack to either #2 target. Long is mostly cut off by the director's Wisconsin zoom but you can see Long's feet at the top to get the point: they're OUTSIDE of the receiver.
This tells the quarterback that Long believes he has help inside. "Where's that help inside?" thinks the man turned on by the undulations of a rill. "Ah, yes, the linebacker currently buzzing the tight end. As soon as my tight end curls beneath that I've got an easy pass."
"I've got you" thinks Randy Rivers, and he releases the ball to the spot his tight end should soon be inhabiting peacefully. The trap is set. And while the quarterback's eyes are fixated on his target, it is sprung.
On these plays the trap coverage isn't just a deterrent—it puts a cornerback in a spot the quarterback's coverage read doesn't expect him to be. Seconds against Michigan's pass rush are precious, and wasting them on a slant that isn't going to develop can cost a down or worse. Giving up a pick because the cornerback gave a false read is much worse.
It's not a panacea. The run defense benefits from two edge guys hanging out near the line of scrimmage and everybody facing the play, but drifting back linebackers still creates space that even the worst team can exploit:
Michigan doesn't have to run these all time time with all their associated blitzes like Don Brown did with BC. Those Eagles were a base Cover 2 team that used trap almost as often. They also ran it out of a 3-3-5 and used all sorts of OLB blitzers to entice a false hot read from the QB thinking the blitz means the slot was abandoned.
Michigan would stay in their Cover 1 blitzing linebackers all day if they could—and maybe the next wave of athletic safeties might give them the ability to dominate slants from a difficult alignment. But having the trap, especially given how much more Cover 2 they're running this year to compared to last, is a nice deterrent to have on film, with little downside and a huge payoff when it catches a QB with a lazy read.