49ers film room: 49ers 2 deep coverages and disguised 2 deep coverages give Seattle offense trouble
The 49ers are still primarily a single high safety defense but some of their best defensive snaps come while play 2 deep safeties.
Though the final score was 27-7 in favor of the 49ers over the Seahawks in week two, the 49ers defense pitched a shutout with the only Seattle touchdown coming when the 49ers special teams field goal unit had a kick blocked and returned for a touchdown in the third quarter. The defense recorded two sacks, both by Nick Bosa, two interceptions (they had three but one was called back on a defensive pass interference), broke up five passes, and had seven tackles for losses.
The defense gave up just 36 rushing yards and held Geno Smith to under 200 yards passing and zero touchdowns. It was the most complete game the team has put together against the Seahawks in quite a while, and the scary thing is there is definitely room for improvement overall even as the 49ers lost Trey Lance for the season due to an ankle injury.
For now, this post is going to look at some of the two deep safety coverages post snap and how some of those coverages disguise other coverages that the 49ers defense played and how they limited the Seahawks offense.
First play, 2nd quarter 10:02, 2nd-and-12 @ SEA 40
Early in the second quarter with the Seahawks facing a second and long situation, DeMeco Ryans called a two-deep quarters coverage shell pre-snap that rotated into cover-1 post snap and forced Geno Smith to throw into double coverage.
The coverage pre-snap looks like quarters coverage with a sim pressure underneath, something the 49ers do often. The coverage is actually cover-1 rat with a 4th rusher coming from Dre Greenlaw (No. 47) lined up in a wide-5 technique alignment. The coverage indicator here is for man coverage indicated by safety Talanoa Hufanga’s (No. 29) alignment over the #2 wide receiver, Tyler Lockett (No. 16) in the slot.
Lockett is running a choice route from the slot and cuts inside on the slant stem because the middle of the field is wide open.
Underneath the coverage rotation, Nick Bosa (No. 97) is the stand-up pass rusher to the defense’s right and has the #3 receiver in trips in man coverage. Fred Warner (No. 54) is mugged up into the A-gap and is the low hole “rat” looking to rob any shallow crossers or slants into his zone.
Greenlaw does not add to the rush for some reason and drops in the low hole zone with Warner and it’s not entirely clear why. However, Smith reads the progressions to the left first and see now throw when he probably should have looked at the matchup on his right with Hufanga covering Lockett. Hufanga has been incredibly impressive through two games but that’s a matchup that should favor Lockett if Smith reads the coverage correctly.
Instead his throw is late over the middle and Hufanga recovers nicely to tip drill the pass to safety Tashaun Gipson who returns the interception for 14 yards out to the 50 yard line.
Second play, 2nd quarter 6:27, 2nd-and-17 @ SEA 32
The 49ers are showing match quarters coverage again as noted by the two deep safeties and the corners playing at nearly safety depth and turned inside. Most likely this is a regular quarters coverage shell with a box call (stump) when the defense gets a fast-3 (RB motion quick to the flat).
In this box coverage, the flat defender, Greenlaw, takes #3 to the flat while Warner looks for a crosser to the inside to “wall” off. The safety and corner look to play any vertical route from 1 to 2 (corner) and 2 to 3 (safety). If there is no vertical then the safety will look to rob any crosser in his zone.
The route concept stresses the underneath rules and gets both Greenlaw and Warner to widen while Lockett breaks inside. Hufanga is watching all of this unfold since there is no threat to his zone immediately. He triggers quickly the second Lockett breaks inside on the glance route and breaks up the pass.
There is another element to this play that works against Seattle and it was their own fault. Niners Nation’s own film grinder Jordan Elliott pointed it out first.
It appears the Seahawks only had 10 men on the field during this play. One of their many blunders throughout the course of this game.
Third play, 2nd quarter 6:21, 3rd-and-17 @ SEA 32
On the very next play, the 49ers would have had recorded their second interception of the game but this play was called back for defensive pass interference on Emmanuel Moseley (No. 4) while in coverage on receiver D.K. Metcalf so I only want to briefly highlight it.
This is a common 49ers coverage in these third down situations. They are in a two deep pre-snap shell that rotates to cover-3 buzz weak on the backside of trips. This is a staple coverage call for them and it led to an interception in week one as well.
The Seahawks tried to exploit this hole in the coverage behind Hufanga by running a deep post route behind him as he rotated down to rob the crosser underneath. Moseley is alone in coverage with Metcalf and makes a nice break on the ball. Had this ball been thrown better by Geno, it would not have led to a DPI and Moseley probably catches it cleanly without running into Metcalf.
Fourth play, 2nd quarter 4:19, 2nd-and-5 @ SF 8
This is the same drive as the two plays above and it did finally end with an interception when Seahawks running back DJ Dallas floated a pass into coverage to D.K. Metcalf in the end zone.
The 49ers are playing red zone quads, a two safety coverage shell that helps a defense cut down on the space it has to defend in the red zone and is another common 49ers coverage in this area of the field.
In red zone quads, Charvarius Ward (No. 7) has quarters coverage responsibility and lets #1 receiver (Metcalf) release inside. He would then zone off looking for any other routes in his zone since Greenlaw has quarter-flat responsibility underneath him.
Ward zones off when Metcalf angles inside and comes up as the force corner in the run, but zone zones off again under Metcalf’s route when he sees a passing posture from Dallas. He can zone off to his quarters responsibility because Greenlaw is in the flat looking for work.
Dallas, who probably could have run this for five yards, floats a pass to the back of the end zone where Ward is waiting. Seattle comes away with zero points on this eventful drive.
Fifth play, 4th quarter 11:57, 1st-and-10 @ SEA 22
Lastly, much like red zone quads above, the coverage pre-snap here is quarters straight across, what is called “quads” in the Vic Fangio tree (for ease of nomenclature). Gipson (No. 31) is the quarters safety away from the passing strength so his job is to lurk around and look for work.
The other quarters safety, Hufanga, would match the vertical of #2 and the corner to the single receiver side matches the vertical of #1. The underneath defenders have quarter-flat responsibilities and widen with anything underneath.
The Seahawks run verticals out of the backfield that stress the quarter-flat defenders horizontally and should give him a window before they reach the safety but the defenders also stay over the top as they widen to take away this window. He eventually checks it down for a 1-yard gain.
Outlook
While predominantly staying a single high safety team to best suit their players skill sets in pass coverage, the 49ers defense is still playing with two deep safeties in a variety of ways even while missing safety Jimmie Ward for an extended period of time. It will be interesting to see how Ryans deploys them in the coming weeks especially coming up in week three against the Broncos and Russell Wilson, who like to challenge with the downfield passing game.