49ers film room: What coverages the 49ers offense can expect to see defensively from the Bears and how Kyle Shanahan might attack them
The 49ers faced Matt Eberflus's defense last season in week seven versus the Colts. Here's what the schematic tendencies of that defense looked like and how the 49ers offense might attack Chicago.
This past offseason, the Bears hired Matt Eberflus to be the head coach and with him, Alan Williams to be his defensive coordinator. Williams was with Eberflus in Indianapolis most recently as the defensive backs coach while Eberflus served as the defensive coordinator for the Colts. The 49ers offense will likely see the same things defensively from the Bears that the Colts threw at them in the Sunday Night Football game last season in week seven.
The Colts are a base 4-3 team on early downs and then do the usual sub-package substitutions depending on second and third down situations. But the interesting thing about Eberflus’s defense is not the personnel groupings on second and third down but their schematic tendencies on those downs and the coverages they play.
Assuming Eberflus does not change his tendencies this time versus the 49ers, and there is good reason to assume that he will not due to the nature of installing a brand new scheme, the 49ers offense can expect to see primarily single high cover-1 or cover-3 on first down, two-high safety coverages on second down (cover-2, cover-5 man, cover-4, cover-6, etc.), and man coverages on third down, either cover-1 man or cover-5 (cover-2 with man coverage underneath).
The single high coverages are to primarily discourage running the football or to stop the run and get the offense to an unfavorable second down and long situation. The two-high safety coverages are primarily designed to disrupt the pass and can leave a defense vulnerable to the run, and the 49ers are very good at punishing teams with the run versus cover-2.
Man coverages on third down are designed to muddy the picture for the quarterback and make it difficult for him to get an easy pass off while allowing the pass rush to pressure the quarterback.
First down - Cover-3 and how the 49ers might attack it
Running game
The 49ers offense had good success on first down versus the Colts last season and attacked their defense with a variety of run concepts and play action passing to move the chains. In the run game, the 49ers were able to use a variety of misdirection zone concepts like windback zone and sift zone to move the ball on the ground.
In the run game, to create space versus an 8-man box on first down, the 49ers called “14/15 Lightning,” or what’s commonly referred to as “windback” zone. The play is designed to take advantage of defensive ends that like to get upfield aggressively. The run action itself looks like counter with the running back taking a counter step before cutting back the other way.
Week 7 2021, 1st quarter 11:02, 1st-and-10 @ IND 28
The 49ers use the windback zone as a weak side run (run away from the tight end side) and never used it with a jet motion until 2021. Here the 49ers use it with a jet motion from receiver Jauan Jennings to the back side while tight end Ross Dwelley sift blocks across to the play side. Since the safety is down in the box to the play side, the play side receiver, Trent Sherfield (#81) has tagged responsibility to block him with Dwelley getting on the edge to block the corner.
For the offensive line, the blocking can look like duo or outside zone depending on the front and the blocking assignments. The center combo blocks the play side defensive tackle and works to the MIKE linebacker while the play side tackle works to the SAM linebacker.
Week 7 2021, 1st quarter 9:52, 1st-and-10 @ IND 28
On the very next drive, the 49ers called the play again but hid the play by not tagging the jet motion with it. The Colts put 8 in the box on first down and the 49ers essentially turned an 8-man box into a 1-man box by isolating the backside defensive end and getting the rest of the front to push toward the initial run action.
Play action pass - Drift
The 49ers also hurt the Colts with play action passes on first down, most notably with the “drift” concept, one of the signature plays in the Shanahan offense. It is a straight drop back play action pass rather than a keeper bootleg. Drift is a quick hitting play that hits in the zone vacated by linebackers flowing toward the run action.
Often the window the quarterback hits is relatively large because the drift route is typically run behind those linebackers closing the line of scrimmage and is there is only one deep safety that cannot play top down that quickly. The drift route is usually run to the backside of the run call but can sometimes be run to the play side and is a quick 7-step vertical stem glance route that breaks quickly inside behind the linebackers.
There are a variety of ways to run it. Traditional drift, drift swirl, and drift stalk. Versus the Colts the 49ers threw two of the three, drift swirl and drift stalk.
Week 7 2021, 3rd quarter 8:34, 1st-and-10 @ SF 10 - drift swirl
Drift swirl is a drift variant with a corner-stop route on the opposite side of the drift route and designed more for attacking cover-2. Here, the 49ers are running “drift swirl” out of an 11 personnel (one running back, one tight ends) grouping from the shotgun against the Colts single high safety cover-3. Garoppolo determines that coverage is cover-3 so he throws the drift route as Deebo hits the open window.
Week 7 2021, 3rd quarter 3:42, 1st-and-10 @ SF 10 - drift stalk
Later in the third quarter, Shanahan called one of his staple shot plays, drift stalk. It is a full field read for the quarterback with a drift route on the front side and a “stalk-rail” by the slot receiver and “drift-takeoff” by the outside receiver to the backside side. The progression goes from drift, to drift takeoff, to stalk rail, essentially giving the quarterback a full field read.
Here, Garoppolo correctly throws the drift route to Deebo as its the first read and he is open. Unfortunately, the play did not count as left tackle Jaylon Moore was flagged for being five yards downfield as the pass was thrown.
Traditional keeper play action
Lastly, on first down the 49ers also gashed the Colts for big gains with their traditional keeper play action passes that are effective against teams selling out against the run with eight man fronts.
I would expect to see some misdirection runs and heavy reliance on play action passing on first down in particular in this game versus the Bears as the 49ers look to make Trey Lance’s life a bit easier as the starter.
Second down - Cover-2/Cover-5 man coverages and how the 49ers might attack it
One play that was detailed above on first down, drift stalk, is also a good play call on second and medium when the Colts came out in two-deep safety coverages. Although it is not the 49ers, the Colts under Eberflus faced the Rams in week two of last season who run a similar offensive scheme under head coach Sean McVay. They were able to hit the stalk rail route on drift stalk versus cover-2, the third in the progression, for a big gain to wide receiver Cooper Kupp.
Week 2 2021, 4th quarter 12:55, 2nd-and-5 @ LA 46
The hook/curl defender to the drift side closes the window to the drift route so quarterback Matt Stafford moves through the progressions and finds Kupp down the left sideline wide open because no one ran with the stalk rail route and the safety to that side was occupied by the drift takeoff route up the hash.
The 49ers have hit this play for several big plays the last few seasons and this game might be a good time to throw it again.
Versus Eberflus’s defense last season, the running game was also effective on second down versus cover-2 because it allows the offense to take advantage of a lighter box by the defense with no safeties in close to fit the run. On outside runs, the defense under a two deep safety shell tends to flow faster to the perimeter to set a hard edge and give the safeties time to get downhill. But Shanahan’s offense has answers for everything.
Week 7 2021, 1st quarter 11:45, 2nd-and-7 @ IND 48
For teams that like to set a hard edge, Shanahan will call “Zorro” or “Zorro Cat”. “The run concept allows the tight end to kick out the wide defensive end or linebacker on the line of scrimmage while the fullback blocks inside and protects the tight end’s defender from any inside move before moving on to the next defender through the hole. Cat” tells the receiver to the play side to block the safety. But “cat” is not tagged here.
Garoppolo checks out of a pass play upon seeing two deep safeties, likely audibling away from “drift.” The 49ers get 7-on-7 in the run and Shanahan will take that all day. Running back Elijah Mitchell gains an explosive run on the play call and is virtually untouched until he reaches the safeties downfield.
I expect the 49ers to mix it up on second down based on how Eberflus plays certain second down situations but if the 49ers can stay ahead of schedule and get to second and medium to short, then they should be able to dictate what they want to do and make Eberflus’s defense vanilla in those situations. Shanahan has answers for everything, especially in high leverage situations and the explosive runs or explosive pass plays are too tempting to pass up.
Third down - man coverage and how the 49ers might attack it
On third down, the 49ers will likely get a heavy dose of man coverage from the Bears. But Shanahan has answer for that too, with route concepts that challenge defenders by creating space either through putting a perimeter defender in conflict or by combinations that stem vertically and break opposite ways against man coverage. The result is usually a route that comes wide open in traffic or open enough for the quarterback to place a throw in space.
One pass concept the 49ers relied heavily on last season versus two deep safeties/quarters coverage teams was a concept called “Bow.” On “bow,” the H back is running a choice route out of the backfield versus the strong hook defender with a “basic” route over the top (dig). The other side of concept is usually paired with a flag/return route combination, a slot choice, or a just a return route as the third option.
Week 7 2021, 3rd quarter 6:18, 3rd-and-10 @ SF 20
The dig/choice side of the concept versus man coverage gives the quarterback an easy read. With the H choice out of the backfield, the defender chases the out cut from the running back, opening a void over the middle of the field for the dig route behind it.
Another route combination Shanahan might get some usage out of is non-play action dagger with a crosser inside and a dagger route by the outside receiver.
Week 2 2021, 2nd quarter 4:28, 3rd-and-10 @ IND 47
McVay, and sometimes Shanahan, pairs this combination with a pivot route to occupy an underneath defender and open space for the dagger behind it or the crosser. The Rams here, facing 3rd-and-4 versus the Colts last year in week 2, have this play called versus Eberflus’s cover-1 man defense. Stafford hits Kupp on the crosser in front of the safety for an 11 yard gain.
Outlook
There’s no predicting what the offense will look like with Lance taking over as the starter but Shanahan has tendencies that are hard to overlook and he is a creature of habit, favoring what worked last time over trying to get fancy the next time around.
The Bears lost Khalil Mack as well. Shanahan will attack the defenders he views as the weakest link and these are some of the ways he might do it with Trey Lance. Add in possibly some zone read, used sparingly of course, and it could serve to make the Bears defense even more static or vanilla on these downs and situations.