49ers midterm marks: Is this one of the best secondaries in football?

There’s obviously room for the 49ers defense to improve. The white-knuckle ride to the finish against the Dallas Cowboys, during which the 49ers blew at least two coverages and nearly the game, could be taken as an alarming final note prior to this bye week and the Nov. 5 trade deadline.

But on the aggregate, the 49ers defense scores relatively well. They rank No. 6 in FTN’s defense-adjusted value over average (DVOA), which measures efficiency and accounts for the strength of opposing offenses. The unit ranks No. 12 in expected points added (EPA), which isn’t adjusted for quality of opponent.

So without big improvement, this 49ers defense won’t be nearly as overpowering as the team’s 2019 and 2022 units. Those finished No. 2 and No.1, respectively, in EPA. But it might not be necessary to reach those heights this season, especially if the 49ers offense can climb back into the top-3 range when star running back Christian McCaffrey returns to action — presumably at some point in November.

The 49ers must simply continue fostering team-wide balance, and the defense’s contribution to this — thanks to some promising early-season development — can come through incremental improvement.

Consider that the 2021 49ers defense, featuring first-year coordinator DeMeco Ryans, ranked No. 23 at this point of that season. The team then enjoyed staggering improvement, checking in at No. 6 the rest of the way. That helped the 49ers turn a 3-5 start into a run that reached the NFC Championship Game.

These 2024 49ers also have a first-year defensive coordinator, Nick Sorensen. Like the 2021 unit, they have struggled on third down (the 49ers rank No. 26, allowing 44 percent of conversions) over the first half of the season. And Sorensen, like Ryans early in 2021, has struggled to dial up effective blitzes. The 49ers rank No. 32 in EPA when blitzing. Even though they bring extra pressure at the third-lowest rate in the league, that’s a clear sign that their coordinator hasn’t yet fully settled into a desired groove.

But if recent history teaches us anything, it’s that the 49ers find ways to play better over the back half. The ingredients to do so are there again in 2024. A look under the hood helps crystallize how the 49ers can make another defensive run this season.

The rightmost column is each lineman’s percentile rank against others at his position in pass-rushing productivity (PRP), a Pro Football Focus stat. It combines sacks, pressures, and QB hits. Darker shades indicate better performance.

Defensive ends are listed in the top half of the chart and defensive tackles are in the bottom half (Robert Beal Jr. and Kalia Davis do not have enough pass-rushing snaps to qualify). The 49ers have enjoyed solid production from both groups, but they can clearly use more depth.

With Yetur Gross-Matos currently hurt (the 49ers expect him back in mid-November), the emergence of Sam Okuayinonu has effectively kept the team afloat at defensive end. But the shakiness beyond him makes it easy to see why the 49ers are again interested in adding an edge rusher prior to the trade deadline.

At tackle, Javon Hargrave is out with a torn triceps muscle. The 49ers hope he can return if they reach the playoffs, but the team could use more interior juice immediately — especially since it still ranks No. 19 in DVOA against the run. That’s why the 49ers are rumored to be interested in 330-pound New England Patriots defensive tackle Davon Godchaux. A beefy player like that could pair well with promising rookie Evan Anderson — who recently earned a full-time promotion to the 53-man roster — to fortify the interior rotation. (It should also be noted that Jordan Elliott, though he’s been one of the least productive pass rushers in the league, has graded well against the run.)

Remarkably, the 49ers rank No. 2 in DVOA against the pass, tied with 2019 for their highest ranking since coach Kyle Shanahan and general manager John Lynch took over in 2017.

While the 2019 defense reached No. 2 thanks largely to its supercharged pass rush, this 2024 unit is clearly more balanced — and the back end is developing in real time. Rookie defensive backs Malik Mustapha and Renardo Green both recently grabbed starting spots. Their excellent play has raised the ceiling of the 49ers’ secondary.

In the above table, cornerbacks are grouped in the top third, linebackers are grouped in the middle third and safeties are grouped in the lower third above. Lower numbers are indicative of better performance in the rightmost two columns.

Cornerback Charvarius Ward has delivered consecutive good games after a slow start. An All-Pro in 2023, Ward remains the anchor of the group, as opposing quarterbacks have thrown noticeably less often in his direction than elsewhere so far. (Ward is currently grieving a tragic death that’s shaken the 49ers organization — his one-year-old daughter, Amani Joy, passed away Monday morning.)

Deommodore Lenoir, who has played 298 snaps at slot cornerback and 116 snaps outside, has emerged into one of the game’s best and most versatile corners.

“D-Mo: All-Pro, nickel corner, outside corner, playing at the highest level possible right now,” star 49ers linebacker Fred Warner said on his podcast. “As long as he keeps doing what he’s doing, All-Pro — he’s gotta be. I mean, come on, the guy’s all over the place.”

Warner, too, is delivering at an All-Pro pace — but the 49ers can undoubtedly use more linebacker help outside of him. Veteran De’Vondre Campbell has struggled against the pass, allowing a 112.7 passer rating into his coverage. The 49ers believe that Dre Greenlaw, who tore his Achilles in the Super Bowl, might return in the coming weeks — though it might take him time to rediscover his old form.

Safety is the spot that’s seen the most in-season improvement already. The 49ers began the season with Ji’Ayir Brown and George Odum starting there. Neither performed well early. But Lynch recently lauded Brown for elevating his game and Mustapha, despite a few missed tackles, has been downright excellent ever since taking over for the injured Talanoa Hufanga.

Safety no longer seems to be a liability for the 49ers, and they’re also hopeful that Hufanga can return from his wrist injury at some point to at least further fortify a room that’s emblematic of this defense as a whole: Though it’s been far from perfect, it’s found a promising combination of veteran talent and rookie energy.

The 49ers hope that Sorensen, as he continues to grow on the job, can fully harness that fusion of talent and deliver a defense that surges toward the top of the league down the stretch — just like Ryans did when both he and the 49ers found their stride late in 2021.