Kurtenbach: The 49ers signing Javon Hargrave corrects John Lynch and Kyle Shanahan’s biggest roster mistake

The big man will be paid big money to fill the Niners' biggest roster hole.

The 49ers have managed their roster as well as any team in the NFL over the last few seasons. That’s why, despite not having an MVP-caliber quarterback, the team has played in three NFC Championship Games in the last four seasons and was a quarter away from winning Super Bowl LIV.

But trading DeForest Buckner to the Colts for a first-round pick that became his replacement at defensive tackle, Javon Kinlaw, was not one of those gilded Niners’ roster moves.

It took three years, but the 49ers finally corrected that mistake.

Buckner isn’t returning to the Niners, but Javon Hargrave is coming to the Bay.

The former Pittsburgh Steeler and Philadelphia Eagle defensive tackle is leaving the commonwealth after agreeing to a four-year, $84 million contract.

It’s big money for a big man to fill a big need for the Niners.

While the Niners’ decision to sign Hargrave, 30, goes deeper than just one game, the NFC Championship Game between the Eagles and Niners showed exactly how much San Francisco needed a 1-technique of Hargrave’s stature.

That forgettable game in Philadelphia was arguably Hargrave’s best as an Eagle. Perhaps that was a byproduct of the Niners’ quarterback chaos, but Hargrave brought persistent pressure up the middle against the pass and was rock-solid against the Niners’ steady diet of runs.

At the same time, Kinlaw — three inches taller and roughly 25 pounds heavier — was lifted off the ground by the Eagles’ (exceptional) offensive line. The NFC Championship Game was arguably the worst game of Kinlaw’s career, though that’s a crowded field without much to counter.

The difference between the 49ers and Eagles that Sunday in Philadelphia wasn’t defensive tackle play, but it might have been the story had the Niners not run out of quarterbacks. I know it was a massive takeaway for the front office — the delta at the 1-technique between the two teams was that wide.

Kyle Shanahan and John Lynch fixed the issue directly. They grabbed the guy who kicked their butts.

Hargrave is one of the best pass rushers in the NFL at his position and will be a perfect fit in the 49ers’ one-gap, straight-attack defensive line scheme. He’s a squatty fellow (6-foot-1, 310 pounds), but he comes off the line like a lightning bolt (34.5-inch vertical leap) and is solid at moving people out of his way.

And while there are some questions about him as a run stopper — he spends some time stepping backward — he’s solid enough and will make some flash plays.

Like Buckner and D.J. Jones, Hargrave is a prototype player for the 49ers’ defensive front. (Jones left for Denver on a three-year, $30 million deal in 2022 — another Niners’ mistake.)

Kinlaw looked like that kind of player coming out of South Carolina in 2019. He still looks like that kind of player on the practice field.

But it’s never translated into games — much less the big ones — and he’s missed too much time. It wasn’t working, and after three seasons, the Niners finally stopped betting on Kinlaw to turn his career around. There was no way his fifth-year option would be exercised before this, his fourth NFL season, so San Francisco opted not to prolong the inevitable.

It’s hard to say right now if the Niners will trade Kinlaw or keep him around for another season. There’s value in having depth in the trenches, but the Niners can save $2.7 million against the cap by offloading him for a draft pick.

Regardless, he’s now a backup, and his time in Santa Clara is limited.

Another fallout of this deal comes at the quarterback position:

If you were hoping that the Niners would acquire Lamar Jackson (through a complicated series of actions, including him not signing his franchise tag), you can now let go of that dream. The Niners’ salary cap situation is fluid, but signing Hargrave makes signing a top-of-market quarterback nearly impossible for the 2023 season.

We don’t know if Trey Lance or Brock Purdy will be the Niners’ starting quarterback in Week 1 of the 2023 season, but we know who will be next to Arik Armstead at defensive tackle: Hargrave.

After three years, a wrong has been righted. And for a team on the cusp of greatness, it’s fair to wonder if this is the move that can get the Niners over the top and into the Super Bowl next season.