49ers film room: 49ers 3rd down offense was the key to beating the Rams

The 49ers offense hit on several big plays on third down to earn their second win of the season and move to 2-0 versus the NFC West with a win over the Rams

The 49ers once again put up a dominant performance on Monday Night Football versus the Los Angeles Rams at home by a score of 24-9. The 49ers defense held the Rams to three field goals, sacked quarterback Matt Stafford seven times, intercepted him one time, and narrowly had a second interception in the end zone that safety Tashaun Gipson could not hold onto.

The story for much of the week though, was how the offense would respond after such an anemic performance the week prior in Denver. In that game, the offense was 1-10 on third down. In this game, they were 5-12 converting third downs, 41%, including one conversion for a touchdown to Deebo Samuel and converting two other key third downs on the first drive of the game, a drive capped off by a 32-yard touchdown run by Jeff Wilson.

When the 49ers convert third downs above 40%, they win more often than not, averaging 45% conversion rate in wins since Kyle Shanahan took over in 2017. They average just 34% conversions in losses since 2017. Under 40%, their win-loss record is 12-27. Over 40%, their win-loss record is 28-17.

There is obviously more that goes into that statistic, but generally, converting third downs keeps drives alive and increases the chances of scoring. Garoppolo converted three big third downs that led to 14 total points, which was enough to win without Talanoa Hufanga’s pick-6.

First play, 1st quarter 5:35, 3rd-and-9 @ SF 41

The 49ers are in 11 personnel (one running back, one tight end) and line up in a 2x2 with stacked receivers to the left before motioning to a trips bunch to the left. The play call is “arches” with a high-low read to stretch the interior coverage.

The Rams are in a sub package zone called “stuff,”  a Vic Fangio coaching tree coverage call for cover-6 (quarter, quarter, half), a tree which the base of the Rams defense stems from. 

Cover-6 in the Fangio tree is a combination coverage with cover-2 away from the passing strength and cover-4 or quarters to the passing strength with the nickel aligned to that side. It is a great coverage that keeps the offense and its passing game in front of the defenders by forcing them to rely on quick game passing concepts.

The underneath defenders' responsibility align with the back end coverage and use match principles to fill in the gaps. For example, the “QTR Flat” defender (quarter flat) would chase the flat route out to the perimeter but would carry them if they go vertical because the safeties are playing over the top of the vertical routes or deep in breaking routes. The vertical hook defender fills in the void in the cover-2 side and the “3 receiver hook” defender carries the third receiver into the pattern.

Garoppolo sends Jennings (No. 15) in motion to the left before the snap and the receivers to the trips switch release. The switch release and shallow crossing routes stretches the underneath coverage horizontally while the dig route from the point receiver, Deebo Samuel (No. 19), gets the dime defender to open diagonally to the dig, giving Garoppolo a window to throw the arches route to Jennings. He hits the window and Jennings gets up field as soon as he tucks it away to gain 10 yards on 3rd-and-9.

Second play, 1st quarter 3:39, 3rd-and-5 @ LA 44

The offense converted another third down here around mid field when Garoppolo found Jennings again for a 12-yard gain before Jeff Wilson’s touchdown run. 

The play call is “Levels” and is a high-low stretch read for the quarterback. In the past, the 49ers have had repeated success with throwing dig routes over the middle but as teams start to take away the middle of the field with more robber and buzz coverages or brackets on 49ers receivers, Shanahan needed to find ways to get other routes the ball. Levels does this with a shallow in-breaking route underneath a deeper dig.

The Rams are in cover-1 “Lurk” where the middle linebacker, Bobby Wagner (No. 45) is the low hole dropper instead of a robber safety.

The Rams erased the deeper dig route by Deebo with the safety coming down to bracket over the top as soon as Garoppolo’s eyes went to that route. He quickly came back underneath to Jennings again on the short under route. Garoppolo pumps the dig and buys a half second of hesitation from Wagner before he comes back underneath to Jennings for the completion and a gain of 12.

Third play, 2nd quarter 3:01, 3rd-and-3 @ SF 43

The Deebo touchdown catch and run came on a nearly identical play to the above pass to Jennings earlier on their first drive of the game.

The Rams are in “Dog-1” coverage, cover-1 with a 5-man rush where both outside linebackers rush the passer.

Pre-snap shows some type of man coverage with 2-deep safeties, automatically eliminating Kittle in the slot on the go route. Jimmy drops back and works the levels concept side to the left where the receivers try to rub or pick the coverage but the Rams are well-equipped to defend it by playing the corner playing man coverage from zone depth. This allows the corner to jump the under route and not get picked. 

Jimmy likely recognized this and threw a high pass that Deebo could go up and snatch over the defender. A pass anywhere lower would have been intercepted and returned for a touchdown. Instead, Deebo grabbed and scored from 57 yards out after he made Jalen Ramsey (No. 5) bounce off of him en route to the end zone.

Quick game concepts to neutralize Rams pass rush and zone and man coverages

Kyle Shanahan is a master at figuring out an opposing defense’s coverage rules and designing game specific plays to attack those rules and take advantage of certain players. He did this twice in the game with the same quick game slant/flat half field concept paired with a backside dig and spot route.

First play, 1st quarter 6:48, 1st-and-10 @ SF 25

The opening play of the script for the 49ers was a called slant/flat to the backside of the formation and the dig/spot to the passing strength.

The Rams are in a cover-1 with a 5-man pressure.

On seeing man coverage, the read for Garoppolo becomes the backside slant/flat combination where he is reading the leverage of the defenders. The man coverage tells him the slant will be open once the linebacker is cleared out with the flat route. As soon Aiyuk clears the linebacker, Garoppolo lets it rip over the middle for a 15-yard gain.

Second play, 3rd quarter 4:17, 1st-and-10 @ SF 27

This is the same exact play, flipped to the right where the slant flat is coming from the right side. The other difference is there is no motion to the slot from the fullback.

The Rams are in drop-8 coverage called “Cubs” in Fangio terminology with two deep safeties. In drop-8 coverage, the corner should carry all of the #1 receiver and linebacker Leonard FLoyd (No. 54), who the coverage bust is on, should reroute the slot receiver and play the curl/flat. If the slot does not go vertical, get to the flat.

The Rams had little reason to believe they were going to see a different play from this formation. NFL players are smart and pick on tendencies and Shanahan probably even baited them a little bit based on the first time they ran this play with Aiyuk out wide outside the numbers. But Floyd for some reason steps upfield at the snap and never recovers. The corner runs with Aiyuk on the slant and the safety closes the window so Garoppolo quickly flings it out the flat where Juszczyk is wide open.

Despite the win, there was still a lot the offense left on the table but the effort was much better as Garoppolo got an extra week with the first team. They should be able to capitalize on a few more of the missed throws, drops, or blown pass and run blocking assignments.