How 49ers Shut Down Rams Run Game
NFL Week 18 - The early years of the Sean McVay era in Los Angeles were defined by a dominant run game. For two seasons, the Rams were among the best running teams in the NFL, barreling through almost every defense in the league with a rare blend of offensive line talent, a star running back, and crafty scheming. The Rams rode that formula all the way to a Super Bowl trip following the 2018 season. It was their identity.
Fast forward to 2022 and the Rams have just lost a Week 18 match against the rival San Francisco 49ers with the division title hanging in the balance because they could not run the ball whatsoever.
It's not just that the Rams did not have a dominant run game like in the past. It's that they did not have a run game that did anything for them at all in this matchup. The 49ers' front held running backs Sony Michel and Cam Akers to just 46 yards on 26 combined carries, most of which went to Michel. Some of that is the Rams' average running back play and some of it is the Rams' offensive line having its worst day of the season, but a good portion of the credit goes to 49ers defensive coordinator DeMeco Ryans for deploying his guys the right way to stymie the Rams' inconsistent rushing attack.
The hallmark of the 49ers defensive front is that they play fast. They want to fire off the ball, create chaos, and count on having enough bodies flying around at top speed to find the ballcarrier early. In this particular matchup, San Francisco's favorite tool was to slant their defensive line a gap away from the direction of the run. For zone-based teams such as the Rams, that can present some real issues. Firing defensive linemen back a gap requires the offensive line to be able to communicate and pick up that movement effectively. If they don't, the offense risks letting defenders into the backfield as well as wasting two blockers on one defender.
Defensive tackle D.J. Jones (93) is the key here. If Jones were just playing to the gap he was aligned in, left guard David Edwards (73) would be able to ride him to the outside and center Brian Allen would be free to work to linebacker Fred Warner. In theory, that would open up a crease for the running back to cut the ball inside behind Jones, assuming the right guard could climb to the other linebacker (Dre Greenlaw, 57). Instead, Jones fires off immediately to backdoor Edwards and slam into him. Jones ends up splitting the two blockers while occupying both of them, which works to both get himself in the backfield and to free up Warner to help clean things up untouched.
As the game went on, the Rams tried hitting on some wider run concepts to stretch things out and hit the outside. On paper, it sort of makes sense that the answer to a team firing off inside and away from a run concept would be to take the ball even further away from that chaos. That may be true if only the defensive tackles are doing it, but if the defensive ends are also slanting away from the run, the offense stumbles into a different set of issues.
The value in outside zone runs is that they threaten the perimeter but allow the running back to cut it back up inside if things sort out the right way. By stunting defensive ends back inside, the defense gets to dictate where the ball goes. Depending on the running back's path or just how much depth the end gets, the defensive end can either cut the play off entirely or push the play even wider than the offense wants it to. Either way, the idea is to create enough disruption off the running back's desired path to give second- and third-level run defenders time to come fill in.
This time, it's star Nick Bosa (97) who unlocks this play. Bosa is initially aligned to the tight end's outside shoulder, which would normally leave him to get combo blocked by the tight end and the wide receiver next to him. However, since Bosa fires off inside right away, the tight end oversets a bit and allows Bosa a free inside track while the wide receiver whiffs at the air where Bosa is supposed to be. The free inside access enables Bosa to get upfield and then work back outside through the block to pry the run wide open, right into the waiting arms of the safety who was rotated down into the box.
Different look, same Bosa. In this case, though, Bosa gets enough penetration into the backfield to cut the play off entirely and force the runner back into a congested run box. As chaotic as it looks, the 49ers get their desired result with Warner (54) flying down and pushing the play back another gap right into the waiting arms of defensive end Charles Omenihu chasing from the other side. When coaches and analysts talk about dictating the other team and playing fast, that clip right there is a prime example.
The soul-crushing part of it all for the Rams is that they started to catch on, but it didn't matter. In this instance, Cooper Kupp (10) feels the stunt coming and only checks the defensive end before climbing to the next level of the defense. Ideally, if left tackle Andrew Whitworth (77) can pin the defensive end inside early, the Rams should be able to hit the play outside since Kupp is actually blocking someone, unlike in the second example from earlier. Whitworth does his job, but unfortunately for the Rams, right guard Austin Corbett (63) failed to take a flat enough angle to get across Greenlaw (57), giving Greenlaw just enough space to hit the gas and catch Michel on the perimeter.
By the end of the game, it was clear the Rams did not have an answer. Not a good one, anyway. L.A. attempted to get into heavier formations, run some duo, and even run a couple of pulling concepts, but those answers were largely ineffective save for one trap call in the second half. Perhaps the Rams should have tried turning to more of those trap concepts to catch defensive linemen flying up the field, but they do not major in runs that feature pulling their linemen, and it's hard to flip that switch in the middle of a game.
As the Rams try to navigate through the playoffs, they have to avoid rushing performances like this one. They do not need to be as dominant as they were in the past, and that isn't a reasonable ask for this roster anyway, but they need to at least run the ball well enough to take some degree of burden off the passing game. Asking Matthew Stafford, or just about any other quarterback, to win a game with the support of 2 yards per carry on the ground is not a winning formula, especially not in the postseason.