The Ohio State defense had an uneven showing protecting a lead against Purdue’s pass-first quick game in the Buckeyes’ 59-31 win. Ohio State opened the first series in cover 4 Meg (the corners in man on the outside).
The Buckeyes were able to force an opening three and out, and were generally successful defending the Boilermakers’ wide field screen game throughout.
But Ohio State’s efficacy waned as Matt Barnes adopted more of a pass-first approach. Even on early downs, the Buckeyes often played what are generally their third down concepts such as cover 2, cover 5 (2 deep safeties with man coverage underneath), or an 8 man dropping cover 3 buzz creating a layered zone approach.
This limited Ohio State’s run game defense, as they were repeatedly down a man in the box. In addition to the pass-first coverage schemes, the Buckeye linebackers often “froze” to play the pass rather than fill their run fits. For instance, below, Ohio State is playing a soft cover 4 quarters to the field and cover 4 meg to the boundary. Both linebackers freeze to play run action, creating distance between the defensive line and second level.
Likewise here, the Buckeyes are in cover 5. Defensive end Jack Sawyer jumps inside to play the pass, while playside linebacker Cody Simon is focused on his man coverage responsibilities on the tight end, leaving no one to set the edge.
This pass-first defensive approach allowed Purdue to use the run game enough to stay ahead of schedule. Ohio State also notably missed Haskell Garrett’s impact at 3-technique defensive tackle, as he was still seemingly limited.
But Purdue’s run success was as much a reflection of the Buckeyes’ strategy than actual run defense execution problems. For instance, on the Boilermakers’ final drive, Ohio State returned to playing more cover 4 or cover 1 (below cover 1 robber) with their linebackers playing downhill, leading to several stuffed runs.
Yet despite the Buckeyes’ pass-first approach, Purdue’ bigger success came with quick hitting passes—in particular targeting the underneath flats—against Ohio State’s cover 3 or cover 4 concepts.
Likewise, below, Ohio State is seemingly playing cover 2 to the 3-receiver side, and cover 4 Meg to the 2-receiver side. With the corner carrying the outside receiver vertical, backup Will linebacker Teradja Mitchell as the weak apex is out leveraged at the snap and needs to immediately get out on number 2 receiver in the flat.
By contrast, Purdue created several of its explosive pass plays in the outside hole against cover 2 (behind the corner and outside the safety). Because Ohio State spot drops in their zone coverage, they were left vulnerable to the deep outside in cover 2 without the weak apex defender over the slot receiver carrying that receiver vertical or at least re-routing them to provide the safety time to get outside.
For example, on Purdue’s first touchdown, the Boilermakers put quads (4 wide receivers) to the boundary to run 3 verticals with a bubble route. Ohio State is in Tampa cover 2, meaning that the Mike (Simon) carries the number 3 (counting from outside-to-in) receiver vertical between the two safeties. But this still leaves two vertical routes against boundary safety Ronnie Hickman, while Will linebacker Steele Chambers and boundary corner Denzel Burke both stay underneath. Again, the Buckeyes would need Chambers as the weak apex to carry one of the routes vertical to prevent Hickman being left two against one.
Similarly below, Purdue runs smash (outside receiver runs a hitch, inside receiver a corner route) to both sides with a middle divider route. This is a classic concept against cover 2 and again provided the Boilermakers 3 receivers against the 2 deep safeties.
The limitations to Ohio State’s spot drop approach are not limited to cover 2. For example, on this third and 10 Purdue explosive below, in their drop 8, 3-buzz scheme, Ohio State is seeking to create three layers to the defense. Ronnie Hickman as the boundary safety thus effectively serves as an intermediate middle of the field safety between the 3 deep and 4 under. But Purdue can still complete the throw because both the deep third corner and curl-flat defender fail to recognize that are no other threats and squeeze the dig route.
Later in the game, Ohio State started playing more quarters to the field and cover 4 meg to the boundary, which did assist with covering the wide flat.
The Buckeyes also mixed in cover 1, which often forced Purdue to throw vertical routes—and where Denzel Burke largely did a nice job preventing David Bell from creating big plays.
But Ohio State continues to struggle at times with rub or pick routes with maintaining different levels in man coverage.
Although Ohio State relatively frequently rushed 3, they had little chance to create pressure regardless of rush scheme because nearly every Purdue pass play was a one-step drop quick concept. For example, even on the incomplete vertical route to Bell above, Aiden O’Connell throws off of one step and Purdue cuts the Ohio State defensive line on the backside.
Purdue’s heavy quick game reliance likewise left Ohio State vulnerable when they did attempt cover 3 hot pressures.
Below, the Buckeyes show cover 4 pre-snap before rolling to cover 3 hot (3 deep, 2 under), with the linebackers crossing to blitz in the A-gaps between the guards and center. But the pressure had little impact and free safety Bryson Shaw got caught looking into the backfield, leaving him beat to the post.
The hot coverage also left Ohio State vulnerable to the quick game to the flats with so little time to get home.
Playing with a lead, Ohio State largely thus settled for not letting Bell beat them one-on-one and forcing Purdue to repeatedly drive the football with quick throws. Although the outcome showed the limits of the Buckeyes’ zone defense, the game is likely not indicative of Ohio State’s defensive scheme or the challenges moving forward.
For example, against the more run-first offenses that the Buckeyes will face (such as Michigan and Michigan State), Ohio State will more likely rely on the combination of cover 4 mixed with cover 3 pressures that Barnes used against Penn State and Nebraska, looking to put the opponent behind schedule where Ohio State can rely on its pass rush (which is critical to Ohio State having an effective pass defense).