The New York Jets. The San Francisco 49ers. Two of the most stacked rosters in the NFL.
These rosters might be stacked, but having a stacked roster doesn’t mean having a perfect roster. There has never been a perfect roster in the NFL.
Visit our New York Jets Analytics page to learn the advanced football numbers.
Even the perfect teams weren’t actually perfect. The 2007 New England Patriots, who went 16-0, only ranked 13th in rushing yards during the regular season, and that came back to haunt them later as they ran for just 45 yards in a Super Bowl defeat.
Every football team can be exploited somewhere. Yes, the 49ers might have the best roster on paper in the NFL today. Yes, the Jets have to travel cross-country to face them in their house. Yes, the 49ers got both of their contract-hungry superstars back on the field.
But San Francisco, like every other team, has holes. Big ones, in fact.
Of those holes, the Jets are built to exploit perhaps the biggest: San Francisco’s run defense.
San Francisco’s run defense could be an issue
The 49ers are coming off a 2023 season in which they finished 15th in run defense DVOA and 14th in yards per rush attempt allowed. They proceeded to struggle mightily against the run in the playoffs; across three games, they allowed 149.3 rushing yards per game and 5.1 yards per carry. So, their run defense was already mediocre, which pales compared to the other parts of the team.
Based on the changes to their defensive lineup since last season, this facet of San Francisco’s defense is poised to stoop even further below the mediocre level it was at in 2023. On Monday, the 49ers will be without many of their best run defenders from last season’s unit.
Safety Talanoa Hufanga was an All-Pro in 2022, finishing fourth among safeties with 19 run stops. He was on track to make his case yet again in 2023, but he tore his ACL in November and missed the remainder of the season. Hufanga returned to practice recently but not in full, and is likely to miss the season opener. In 2023, he earned a 77.1 run defense grade at Pro Football Focus, which ranked fourth-best among the 49ers’ starters.
Fellow safety Tashaun Gipson was also a valuable contributor against the run in 2023, posting a 79.5 PFF run defense grade that trailed only Nick Bosa and Fred Warner among the team’s starters. Gipson left for Jacksonville in free agency this offseason.
Also heading to Jacksonville in free agency was defensive end Arik Armstead, an inside-outside tweener who provided a formidable edge-setting presence on run downs. While Armstead did not grade out too well against the run last season (59.8), he’s graded at an elite level in the past, and his presence remained valuable for the 49ers in 2023, as they allowed 3.7 yards per carry with him on the field versus 4.5 with him off.
The 49ers will also be without Dre Greenlaw, who started 30 games at linebacker over the past two seasons. Greenlaw had a solid 70.9 run defense grade last season. He tore his Achilles in the Super Bowl and remains on the road to recovery.
San Francisco’s replacements for these players do not seem poised to replicate their impact against the run.
Hufanga will likely be replaced by 30-year-old career backup George Odum, who had a 65.0 run defense grade in 2023 and has never been above 68.5 in his six-year career. Not bad, but not close to Hufanga.
Greenlaw’s replacement will be ninth-year veteran De’Vondre Campbell, a former All-Pro with the Packers. However, Campbell is better known for his pass coverage. He’s posted a run defense grade below Greenlaw’s 70.9 in seven of his eight seasons, including marks of 67.7 and 60.3 over the last two seasons.
While he is not a direct replacement for Armstead’s role, the 49ers have a new starter on the edge in Leonard Floyd. The former Bears first-round pick has developed into a consistent pass rusher, recording 39.5 sacks over the past four seasons, but run defense is not his forte. Floyd had a 56.1 run defense grade in 2023 and a 58.3 mark in 2022. His run defense grade has declined year-over-year in five consecutive seasons, and now that he’s about to turn 32 years old, there’s a good chance it will dip once more.
The only promising replacement is second-year safety Ji’Ayir Brown, who had a fantastic rookie season. The third-round pick took over for Hufanga at the end of last season and recorded a 77.5 run defense grade. Set to be a starter this year, Brown is a tantalizing young piece for the 49ers.
Overall, though, you have a run defense that was already mediocre in 2023 and lost many of its best players. The 49ers are poised to have a mediocre run defense in 2024, and in Week 1, they will face a Jets team with aspirations of fielding one of the most dominant rushing attacks in football.
With a running back earning No. 1 pick consideration in fantasy drafts, an offensive line that is overflowing with talent, and a quarterback who will force defenses to lighten the box, the Jets are built to be a devastating team on the ground. That could spell trouble for a San Francisco defense facing major question marks in that phase.
So, we now know that New York’s rushing offense has a favorable matchup against San Francisco’s run defense. That’s all well and good, but to make the mismatch count, you need to have the right plan.
What can Nathaniel Hackett do to ensure the Jets fully maximize this matchup?
Where is the 49ers’ run defense weakest?
While it has been four seasons since Robert Saleh coached the 49ers’ defense, their defensive system remains mostly the same. Therefore, Jets fans should be familiar with the strengths and weaknesses of the 49ers’ scheme, as they are highly similar to those of the Jets’ scheme. Niners tight end George Kittle recently said that facing the Jets is “like playing our own defense.”
Kittle cited the “wide nines” and “the penetrating defensive line” as two of the main schematic similarities between these defenses. Jets fans know that while there are major benefits to those two factors in the passing game, the small cost is that offenses have had success against them with power runs up the middle.
With the defensive ends out wide, there is extra room to run up the middle, and that is exacerbated by the two defensive tackles playing with a downhill, pass-rush-first mentality rather than focusing on plugging their gaps. As a result, the Jets have struggled against draw plays, trap plays, pin-and-pulls, or any type of inside-threatening run concept that punishes the core philosophies of the Jets’ defensive line.
All of that applies to San Francisco as well.
The numbers back it up. According to NFL Next Gen Stats, the 49ers allowed 0.02 EPA (Expected Points Added) per carry on runs directed inside of the tackles. That ranked 31st in the NFL, better than only the Panthers and one spot behind the Giants.
For perspective, the league average on inside-the-tackles runs was -0.11 EPA per carry. Basically, running inside is generally not supposed to be very effective for NFL offenses (compared to the average offensive play, when including passing plays), but against the 49ers, the results were positive.
Conversely, San Francisco’s speedy defense was far more respectable against runs directed outside of the tackles, ranking 14th-best with -0.07 EPA allowed per carry (better than the -0.06 league average).
It’s clear that, from a schematic perspective, the 49ers’ weak spot is up the middle. But does that also apply to the talent on their roster?
Yes.
San Francisco’s starting defensive tackle pairing features Javon Hargrave and Maliek Collins. Hargrave is a Pro Bowl-level pass rusher, and Collins consistently generates pressure at a solid rate, but both players are weak against the run. Hargrave had a 49.0 run defense grade last season. Collins was at 45.6 with the Texans.
Even the 49ers’ two backups on the inside are weak against the run. Jordan Elliott (45.5) and Kevin Givens (46.5) make it four-for-four with sub-50.0 run defense grades.
The Jets’ gap-blocking offense is the perfect recipe
With all of that in mind, Hackett’s plan should be simple: pound ’em right up the gut.
In recent years, the Jets were not adequately equipped to achieve that goal. The Jets were a zone-blocking team that generally preferred athletic linemen rather than tenacious, powerful ones. They were better suited to run the ball outside, not downhill.
But heading into 2024, the Jets seem poised to greatly increase their reliance on gap-blocking concepts. New York’s offseason additions at offensive line and running back pointed to a likely change in schematic philosophy, and in the preseason, they showed hints that strongly suggested we’re going to see a much different run scheme this year.
These are the exact concepts that have hurt their own defense, and thus are equally suited to hurting San Francisco.
Gap concepts are designed to hit one particular gap, making them ideal for exploiting aggressive defensive lines whose movements can be anticipated. They take pressure off the running back’s vision and decision-making, allowing him to focus on hitting the hole. In turn, it puts more pressure on the offensive line to execute, as they have to open up that one particular hole for the play to work. Three skills are key from the linemen: down blocks, double-teams, and pulls. Raw power is important, as you must be able to generate movement and dig defenders out of the designed hole.
While gap concepts can go outside, they do tend to go inside more often than zone concepts, which is why they are a good choice against teams who are soft up the middle.
On the other hand, zone concepts are designed to have all of the blockers move in one direction, creating a natural flow that puts the onus on the running back to choose the best hole. The linemen’s job is to allow the defenders’ positioning and momentum to dictate their blocks. If he goes outside, push him outside, and if he sits back side, pin him there. Due to the reactive nature of linemen’s responsibilities on zone plays, athleticism is paramount; you need fluid hips to pin defenders to the back side and good speed to get out on the front side.
San Francisco is loaded with athleticism and speed on defense, making them better suited to defend zone plays – particularly outside/wide zone. On zone-blocking concepts, it’s less about moving defenders and more about getting in between them and the ball. It’s a contest of athleticism that doesn’t challenge the defense’s raw power as much as gap plays. These plays are great against teams that lack speed, tackling ability at the second level, and talented edge defenders, but the 49ers have all of that.
Gap runs up the middle will be New York’s recipe for success on Monday night. Luckily, the Jets are oozing with talent in that very specific area.
With the additions of John Simpson, Morgan Moses, and Tyron Smith – all of whom have fared better as gap blockers than zone blockers – the Jets are built to thrive on the same pin-and-pull, draw, and trap concepts that have been their nemesis in recent years. Simpson and Moses, both known for their power, already succeeded in an elite gap-blocking run game over the past two years with Baltimore. Smith is one of the game’s best pullers. Joe Tippmann and Alijah Vera-Tucker have the athleticism to thrive in zone, but both are just as physical as they are athletic.
Couple all of that blocking talent with Breece Hall’s wildly improved efficiency in gap plays (6.2 YPC for career) versus zone plays (3.7 YPC), and the Jets are set to have a devastating old-school power run game.
For examples of how the Jets can punish San Francisco, they can look to old nemesis Bill Belichick, who did a great job of exploiting the Jets’ schematic weaknesses against the run.
On this draw play, watch how the defensive ends widen and the two defensive tackles shoot their gaps rather than holding their ground. This naturally creates a giant hole up the middle. The delayed handoff helps to further exploit the defensive line’s aggressive mentality.
San Francisco had trouble with gap-blocking teams last season. Including the playoffs, each of their three worst games in terms of rushing yards allowed were against teams who ranked top-10 in gap run frequency:
- Week 15 at Cardinals (51.8% gap rate, 8th): 234 yards allowed
- NFCCG vs. Lions (46.8% gap rate, 10th): 182 yards allowed
- Week 6 at Browns (61.1% gap rate, 3rd): 160 yards allowed
To take it a step further, eight of San Francisco’s 10 worst games in terms of rushing yards allowed were against teams ranked top-10 in gap run frequency, while nine of their 10 best games were against teams outside of the top 10 in gap frequency.
We shall see where the Jets’ gap rate ultimately ends up, but their preseason rate of 51.9% would have ranked eighth-highest in the 2023 regular season. I would expect that rate to hold in the regular season, if not increase.
Here is an example of the 49ers struggling with a power run up the middle. The Lions run a classic “Duo” concept, which features double teams at the point of attack. The center and left guard create substantial movement on Javon Hargrave (No. 98), carving a big hole up the middle.
David Montgomery failed to create anything beyond what was blocked up for him, but Breece Hall has the speed and elusiveness to beat that safety and turn it into a long touchdown.
The Jets’ run game has a major advantage against the 49ers’ run defense going into Monday night. It all centers around the Jets’ new power run game against a 49ers team that is susceptible to power runs, both in terms of their schematic structure and their roster makeup.
Look for the Jets to try and pound the rock up the middle all night long.
