Many coaches and fans believe that a man pass coverage scheme leads to better run defense. This is because--the thinking goes--primary run defenders are given more freedom to attack the run with aggressiveness, while primary pass defenders focus on covering receivers. If the defensive coordinator is willing to play with limited help over the top, it also allows the defense to load the box to stop the run. For example, in a common "man free" scheme against a traditional two wide receiver set, the two cornerbacks lock on the wide receivers and the safety plays over the top, while the remaining 8 defenders can play close to the line to stop the run.
Such thinking has extended to the defense of spread offenses. Against a "spread to run" opponent, one strategy is to lock in man coverage on the receivers to take away quick patterns, while giving your team a numerical advantage inside the box. Because of this numbers advantage, the defense can be aggressive with run fits, blitzes, and stunts. The numbers advantage can often be achieved even while keeping two safeties on the field, because of pattern matching principles, which allow outside linebackers to stay closer to the box and safeties to play the run more aggressively (further explained below).
Man coverage principles can, however, weaken a run defense.
The primary reason is because it is difficult for a defender to play man coverage while maintaining proper run discipline and pursuit. With responsibility focused on a receiver, a defender is more likely to be run out of a play by a receiver simulating a pass pattern. Edge defenders will have difficulty preventing the ball from being run outside when they also have to defend routes that take them inside. The offense can more easily manipulate defensive alignment in order to break contain. For example, a trips formation to one side with a tight end on the opposite side may lead to only a linebacker standing between the offense and the sideline on the tight end side of the field. If the offense can break that contain (against a linebacker instead of a defensive back), they have a big play on their hands.
Enter California and their prolific offensive coordinator, Tony Franklin, against the Oregon State Beavers. Oregon State under Mike Riley was one of the most sound and well coached programs in the country, consistently fielding rugged, overachieving teams. They came into the game with a strong pass defense that appeared to match up well against Cal's powerful air attack. In this game, however, their man principles hurt their ability to stop Cal's running game.
As one can see below, Oregon State lines up in a two safety shell against Cal's four wide receiver (2x2) offensive set. The outside linebackers split the distance between the #2 receivers (the 2nd receiver from the outside) and the offensive tackles. The safeties play on the inside shade of the #2 receivers, while the cornerbacks line up in press coverage on the wide receivers.
What is not clear is whether the Beavers are playing true man coverage, or pattern matching principles. Pattern matching is a method by which particular defenders lock in man coverage against certain offensive patterns, while playing zone against others. For example, a typical pattern matching scheme is for the outside linebackers to cover any short out route by a #2 receiver in man coverage, while they would re-route any vertical stem by the #2 receiver and look to help in the flat. The safety would cover any vertical route (more than 7-10 yards) by #2, while the cornerback would cover any vertical route by #1. In many ways, pattern matching combines the best of both zone and man coverage--nobody has to cover every pattern, so they can be more aggressive against the run, while maintaining the benefits of man coverage against the pass.
Teams such as Michigan State (which bases out of a 2 safety, cover 4 pattern matching defense) and the Seattle Seahawks (a primary 1 high safety [Earl Thomas, perhaps the best safety in the game], cover 3 defense) have built dominating defenses on such principles (see this piece for an in depth explanation of how such principles aid cornerback play). Michigan State's defense has--in particular--taken the coaching world by storm. The Spartans have laid out a blueprint that allows safeties and linebackers to play the run aggressively (thus effectively creating a 9 man box) while having less fear of being burned in the passing game, because they do not have to cover every pattern by a particular receiver. The Spartans defenders are terrific at reading run or pass and reacting accordingly. Unfortunately for the Beavers, even if they were using such a pattern matching scheme (it is unclear if they were), they were too quick to jump into man principles on many occasions against Cal. Franklin often exploited this over-zealousness, both on run/pass neutral downs and on obvious passing downs.
Whether or not the Beavers were playing man or a pattern matching zone on this play, their defenders locked in on receivers in man coverage as soon as those receivers ran their routes. When Cal ran the ball, Oregon State was left with little support.
- Oregon State is lined up in a 2 safety shell, with safeties on the inside shade of the #2 receivers, outside linebackers splitting the distance between #2 and the offensive tackle, and the cornerbacks in press coverage. With the outside linebackers so close to the box, Oregon State would appear to have a numbers advantage against the run. Their front seven remains close to the ball (though both outside linebackers are slightly outside the box), while Cal only has 5 offensive linemen to block the interior, with no lead backs or tight ends to help counterbalance the Oregon State front.
- Cal quarterback Jared Goff turns and immediately hands to running back Daniel Lasco. There is no initial pass fake from the backfield action (though Goff does fake setting up for a pass after he hands the ball to Lasco).
- After the ball is handed off, we see that the Beavers have already lost both cornerbacks. Both have their backs turned, defending pass patterns. Even worse, their playside outside linebacker has turned his back to the ball, and is covering a slot receiver on a quick out route. Both safeties are eyeing the slot receivers.
- As Lasco reaches the line of scrimmage, the Beavers have lost their advantage. The playside outside linebacker is almost beyond the hash marks, still chasing the quick out route. The playside safety IS outside the hash marks, most likely looking to help with the vertical route being run by receiver #1 to his side. Both cornerbacks are completely removed from the play, as is the weakside safety, who is also likely to be helping with the vertical route by his #1.
- Notice that the Cal offensive line hasn't manhandled anybody--they have simply put bodies on bodies. The Oregon State middle linebacker has done a decent job of filling his gap--but there is no help from the playside outside linebacker or safety to squeeze the play, and Lasco easily scoots outside. No support means that nothing is squeezed to the middle of the field, effectively rendering meaningless any pursuit from the Oregon State front.
- Lasco heads towards the secondary. The playside safety has now reacted, but--as with his middle linebacker--he has no help from his opposite safety, allowing Lasco to veer easily away from his pursuit.
- As Lasco cruises into the end zone, neither the backside safety nor the backside cornerback has come into view--both have been occupied by the #1 receiver.
Every defense has its weakness. This post is not meant to say that man coverage and man principles cannot produce great defensive football. The aim of the post is to point out a (perhaps) hidden weakness in man coverage that many fans and coaches do not consider.
Keegan Dresow is the head coach of the Avedøre Monarchs of the Danish American Football Federation, the author of Offensive Football Systems, and the operator of totalamericanfootball.com.