Chip Kelly on scouting/developing counters pic.twitter.com/S5tM472eC9— PickandPop (@PickAndPopNet) October 29, 2017
Let's start briefly with a high level idea of the drag route and the role it plays in the offense. Crossing routes are different than say a Dig or an In route because the stem never truly threatens the defense vertically. Rather, the offensive player is immediately gaining ground laterally across the field (the depth of the route will alter the slope of the stem).
I linked above a number of 2 person concepts that included a crosser. Some of the one man routes that teams utilize (often with a tag for the other receivers, like double post) include Y-Cross and what is known as a "Shallow" concept.
Originally, the Air Raid offense utilized crossers as a way to make up for a lack of speed. Essentially, the WR gets a running start while the defender still needs to be able to read the defense and react. However, as teams with better athletes started utilizing crossing routes, they soon realized that it had the added benefit of being able to get your speed in space and threaten the opposite side of the formation (where teams often roll coverage to the formation).
OSU and the Mesh
The mesh has been the talk of the town for the OSU offense this year. You can't throw a stone on the internet without hitting someone that wants to talk about it. "Oh sure, throw pillows are great, but what about that Buckeye pass game? Those crossing routes are awesome," is what I assume is happening at other websites. Usually I "link elsewhere" at the ends of these posts, but really...
Mesh as a concept has been broken down here and how OSU runs it broken down so well elsewhere that it doesn't even really seem appropriate to reiterate, so we'll leave it as this.
Defending the Drag or Mesh
There are about a million and a half (give or take) ways to try to defend these routes. Often times the best way is to have defenders that are smart and can key the far side of the field and look for these crossers.
If you have a "Rat" LB, he can't have tunnel vision into the backfield and needs to wall off the crossing route to disrupt the timing and the flow. If you have a "Robber" safety, he needs to be able to work down onto the crosser at an appropriate angle. Many teams will "Cross" cover these routes with their DBs or find other ways to bracket the receiver with an inside leverage component.
In your man you can communicate the threat to the far side of the field and switch in the middle.
On the simpler side you can run zone. But again, the key to any zone is to be smart with your eyes, cover the man not grass, or else the receiver can settle in the voids. But, for instance, cover 2 can allow you to wall off crossers and take away those underneath threats.
If you don't think you can beat the offense straight up, you can run some more exotic coverages that give the appearance of guys being run off or feature deep coverage working short, such as a Cover 2 Robber.
And of course, match up zones can work wonders to confuse the QBs reads and get every guy covered. Lots of options.
So now I've outlined both how OSU runs these crossing routes and how teams will generally try to defend them if their base isn't working. But what do you notice about all these attempts at defense "when the base isn't working"? They mostly involve: 1) A defender (typically a LB) trying to wall off or catch the crossing defender by getting even with them vertically (because the drag doesn't threaten vertically); or 2) a defender driving down on a route from deeper in coverage.
In both of those cases, the defender is going to want to "cheat" in order to take away the drag. In both of those cases, the defense has sacrificed it's ability to defend vertically in an effort to mitigate the threat working horizontally. The "Drag and Go" is just what it sounds like, it gives the impression of a drag route (horizontal threat) with the initial stem and converts into a seam/post and attacks vertically, taking full advantage of the defenses reaction.
Looking at the Film
There are really two different ways you can utilize a "drag and go" type concept. You can read it, or you can call it pre-snap. Either way doesn't necessarily change the routes around the concept, but it does change how the offense operates.
Many teams, for instance, will read on a Y-Cross concept. They want to get below the playside LB and above the MIKE and then read the safeties. 2-High safeties and a parting of the seas and you attack it deep. Otherwise, stay the course.
The downside here is that the receiver is now spending his stem reading the defense instead of selling the cross. He is less inclined to sell the drag route by getting up to full speed because he is tasked with making the correct read at the correct time. And his eyes do nothing to dictate the defenses reaction. Instead, the offense is merely reacting to the defense. No harm in that, that's the whole basis of RPO and other read teams, but it doesn't give you the chance as much to dictate the defense, which sometimes has its benefits.
OSU on the other hand, is likely only reading this pre-snap. They see that "TASTY" coverage, and they are going to attack it.
Get to the LB full speed, see him try to "collision the crosser", stick a foot in the ground and hit the seam.
Now, look at the other routes, these other routes technically work with a crossing route too because they pull the coverage deep. But notice both are trying to pull the safeties wide more than anything. The nearside WR is running a corner route to draw the safety into coverage and then pull him wide. The far WR is running the same. Draw the safety in coverage and run him wide.
And really all this is Base 7 Y Vert Read, but with makeup on the pig. It's a basic concept, but you are utilizing the makeup to force the defense to react down prior to attacking vertically.
Jim Light also posted some examples of Michigan running the same basic idea:
X Dip. Great red zone play versus a team whose bunch check is "Lock & Level." Motion to bunch forces the base check. pic.twitter.com/q1YxAUTXkd— James Light (@JamesALight) May 27, 2018
X Dip: pic.twitter.com/Jr3vDZpUFs— James Light (@JamesALight) May 27, 2018