Reuben Foster Excels in the 49ers’ 4-3 Under, Cover 3 Defense

[dt_divider style=”thick” /]

When the San Francisco 49ers face off against the Carolina Panthers and elite middle linebacker Luke Kuechly, a future great linebacker of their own will take to the field. Reuben Foster was the #1 inside linebacker before the draft, yet new general manager John Lynch managed to steal him at the bottom of the first round due to draft-time character concerns. In the preseason, Foster demonstrated the ridiculous value that Lynch got with the 32nd overall selection. His play was to such a standard that rumors of Navarro Bowman being on the trade block emerged.

The arrival of defensive coordinator Robert Saleh, exSeahawks defensive quality control coach and former Jaguars linebackers coach, has brought the Pete Carroll 4-3 under, Cover 3 Press defense to San Francisco – a system reliant upon a strong linebacker. Take, for instance, how disappointing the Oakland Raiders have been while trying to implement elements of the defense under Ken Norton Jr.. Or look at the Jaguars, where a lack of range from the Mike spot has hurt them.

Against the run, the middle linebacker must have range and instincts. They have to be able to get from sideline to sideline and scrape, but must also stay disciplined with their run fits. Getting downhill and physically is also a necessity. Linemen are going to try get onto linebackers, but the linebackers need to fight through that, fill their gap, and get to the running back.

The 49ers defensive coverage will frequently be a 3 deep, 4 under zone, meaning the three linebackers cover underneath alongside the strong safety. The coverage will give up catches underneath, but relies upon the defenders being quick enough and physical enough to make the tackle while keeping yards after catch to a minimum: They must rally to the football. The theory is that teams will not be able to sustain a drive with underneath catches only.

In their third preseason game against the Minnesota Vikings, where San Francisco’s starters played the most snaps, Foster put on a linebacking clinic from the WILL position. This extended to showing his ability in coverage to limit yards after the catch and flashing his physicality and range against the run.

[dt_divider style=”thick” /]

Goodnight Mr. Cook

The first example came on the opening offensive snap. The Vikings are in 11 personnel, with a shotgun formation that has tight end David Morgan (#89) and running back Dalvin Cook (#33) to the boundary side and wide receiver twins to the field side. The 49ers respond with a nickel, Cover 1/Cover 3 press look, with strong safety Eric Reid (#35) in the box – their staple for the season.

Following quarterback Sam Bradford’s (#8) signal, it becomes immediately clear that San Francisco is in man coverage, with both cornerbacks executing man turns and linebacker Navarro Bowman (#53) playing a hook zone over the seam. Bradford first looks to the left and the 5-yard dig route from Laquon Treadwell (#11) which is covered. He comes off this quickly, attempting to look off defenders by keying in on the deep routes from his tight end and flanker. Bradford then quickly hits the Cook’s after holding the ball for around two seconds.

[jwplayer file=”″ image=””]

You can see why Bradford took this option. Foster is the man assigned to cover any route from the running back. When the ball leaves Bradford’s hand, the linebacker is 8 yards away from Cook. As a quarterback, one would feel confident in the elusive, speedy running back to make the only defender in the vicinity miss in space. Then it should be all open field and yards after catch.

Yet Foster’s excellence stops this play for a loss. He displays the correct amount of caution in his angle before the ball is thrown, sensible in case Cook’s route transforms into a wheel. He also manages to come 5 yards downhill and outside without getting caught up in the traffic of the tight end’s route. Once he is in position and it is clear Cook is only running a swing, he breaks on the ball without needing to look at the quarterback.

The closing speed he flashes is ridiculous. He breaks just after the ball is thrown yet gets there as it arrives. He hits Cook hard, but importantly with superb form; using leverage, hitting him with his shoulder and wrapping the receiver up. The combination of speed and lowness sees his fellow rookie thundered to the floor.

[dt_divider style=”thick” /]

Mesh Killer

The mesh concept is a common scheme run against Cover 3 looks, because it is designed to get the ball into the hands of receivers quickly and then give them running room. Cover 3 teams face it often. However, if the defense can rally to the ball and limit yards after the catch, it makes the passing concept less favorable to the offense. Take, for instance, Super Bowl XVIII where strong safety Kam Chancellor smacked Demaryius Thomas running the mesh. Demoralising.

Here, the Vikings run a mesh to try and kick-start their two-minute drive at the end of the first half. The offense is in a 10 personnel shotgun formation. The 49ers are in nickel personnel showing a clear Cover 3 off, with both of their cornerbacks playing a look-in technique and their free safety positioned so high that he is off the broadcast screen.

Minnesota can expect the mesh to have considerable success. There is no press to disrupt the timing of the routes, and the second-level defenders start with 6 yards of depth before their zone drops. Once the ball is snapped, Laquon Treadwell (#11) runs his route over the middle. He has the option to either continue his crossing pattern (if the coverage is man) or nestle down on his route (beneath the zones). He correctly settles underneath.

[jwplayer file=”″ image=””]

Bradford again attempts to look off defenders by glancing at Y receiver Stefon Diggs’ (#14) vertical route, but he wants the crossers. He throws it to Treadwell, who makes the catch.

This is here where Foster impresses again. Diggs’ intermediate route is designed to push him deep and clear out space for Treadwell, but the linebacker reads the play perfectly. Before Treadwell has had a chance to fully turn, Foster is breaking downhill hard from his hook zone. He smashes him backwards with great form. Again; the closing speed, play recognition, and power is remarkable.

The defense is perfectly happy giving up a 3-yard reception like this. It gave them the chance to intimidate and dominate.

[dt_divider style=”thick” /]Guard Toppler

A 4-3 under is designed to primarily stop the run first, and the linebackers are integral to achieving that goal. With 10 minutes remaining in the first quarter, Foster illustrated what he can do to an offense’s run game.

Down by a touchdown facing a 2nd and 7 with plenty of football to be played, the Vikings can realistically call an endless list of plays here. They motion tight end David Morgan (#89) from the slot to the closed side of a bunch on the left. This sees the linebackers shift and strong safety Eric Reid (#35) join the defensive front to form an eight-man box. The offense has a gun bunch formation, but with 12 personnel on the field.

San Francisco is in a 4-3 under front, with SAM linebacker Eli Harold (#57) down at the line of scrimmage, responsible for the strongside D gap. Against the run, each player in the front is responsible for a gap. Foster, weakside linebacker, is playing in a 00 alignment, and is assigned the weakside A gap. Next to him, Bowman (#53), is the middle linebacker but is playing in a 40 alignment. His initial responsibility is the strongside B gap.

[jwplayer file=”″ image=””]

The Vikings snap the ball and run a toss to the field and strongside. As soon as the ball is snapped, Foster does a terrific job reading the play and flowing toward the sideline. He does not over pursue, maintaining the correct landmark to fill his weakside A gap when/if required. With SAM linebacker Harold crackback blocked out of the play by tight end Kyle Carter (#86), Bowman is left responsible for outside contain.

Bowman comes downhill and attempts to cut left tackle Phil Loadholt (#71) out of the play. While he does get him into the ground, he is also left on the floor. This creates a crease for Cook, particularly with left guard Jeremiah Sirles (#75) in front of him.

Foster, though, blows this brief opportunity. He dominates his gap, getting low and hitting Sirles with his left shoulder into Cook. This disruption trips Cook as he also stumbles into Loadholt, forcing the back to go further outside where he is met by cornerback Dontae Johnson (#36) – Johnson is given the opportunity to get back into the play by this delay, after he was initially caught up in a cut block from Morgan.  

Foster, following his hit, brilliantly manages to stay on his feet with a hop over the wreckage. He again sifts through the trash and joins Johnson’s challenge, rallying to the ball and gang tackling Cook out of bounds with some help from safety Jaquiski Tartt (#29).

I hear you. Yes, the preseason caveat is present. However, the traits that Foster showcased are ones that directly translate to ‘real’, competitive football – just like his time at Alabama. He proved that he is an ideal scheme fit for the 49ers defense, and that he can be truly dominant in the NFL. Don’t believe me? Just watch #56 this Sunday…

Follow Matty on Twitter @mattyfbrown. Check out Matty’s other NFC West work here, such as, what Gerald Everett brings to the Rams and how the versatility of Haason Reddick and Budda Baker fits in Arizona.

Want more Inside the Pylon? Subscribe to our podcasts, follow us on Twitter, like us on Facebook or catch us on our YouTube channel.

Leave a Reply

Your email address will not be published. Required fields are marked *