Routes 49ers can go in free agency, draft to complete new 4-3 D-line

Change is in the works in Santa Clara, and one of the first orders of business by the remodeled and reinvigorated 49ers is flipping the defense from a 34 to a 43.

There’s a lot left to be revealed – namely who starts and where – but we can estimate what they have and what they’ll require in order to successfully make the transition.

To begin, the last two first rounders, Arik Armstead and DeForest Buckner, should be part of the rebuilding plan. Not only are they talented, each experiencing moments of individual triumph, but the 49ers have spent a lot of capital between them.

Additionally, at 23 and 22 years old, their upside is still undiscovered and they’re raw enough to reprogram for this scheme.

Moving on, former Texans and Dolphins defensive tackle Earl Mitchell enters the picture, having signed a four-year, $16 million deal. However, he’s missed significant time the last two seasons and has never started a full 16-game schedule in his seven seasons with two NFL teams. A skilled run-stuffer, Mitchell will replenish the depth vacated by Glenn Dorsey and Ian Williams.

Mike Purcell is back as a gap-shooting rotational defensive tackle, receiving a one-year tender from the team on Monday.

Quinton Dial is still under contract and may be better as an interior defensive lineman in a 4-3; as may Aaron Lynch as a 43 end. That said, it's hard to see Lynch as the answer on the edge. The 49ers need a more dominant source of pass rush. He’d be better as a long-limbed 43 OLB/rotational end combo that provides extra pass rush. It also wouldn't be a surprise if Lynch was traded.

All told, it looks as if the 49ers have two starting spots to fill on the D-line.

And according new coordinator Robert Saleh’s scheme, seen in both Jacksonville and Atlanta, and well-illustrated by Matt Barrows of the Sacramento Bee, the two occupied starting spots may be Buckner at left defensive tackle and Armstead at left defensive end. That would leave the 49ers without a RDT/NT and LEO, which would be the main source of pass rush.

Scripting multiple options, this is the line we’ll aim to finish: TBD LEO – TBD NT/DT – Buckner – Armstead

Step 1: Finding a nose tackle

Route 1: Invest heavy

The Chiefs are in danger of losing Dontari Poe to free agency, and Eric Berry's drawn out negotiation which led to a massive $78M deal from Kansas City can't be helping matters. If Poe hits the market, the 49ers could swoop in, flash cash and plug him into the nose tackle spot. The alternative, of course, is Brandon Williams of the Ravens. He is the other big fish John Lynch could look to land as he works to change the perception of the 49ers. Either would be a marquee addition at nose tackle, giving the 49ers three upper echelon starters even before the draft.

There aren’t any true nose tackles worthy of the 49ers' pick at No. 2 overall. However, Jonathan Allen and Solomon Thomas, listed as defensive ends and largely perceived as top-five prospects, are both capable of playing on the interior line. They just couldn't be pigeonholed there.

So, if the 49ers are going to invest heavy at NT, it seems right to assume it’d be a position solved in free agency.

Route 2: Seek value

The 49ers could rely on Mitchell, the veteran free-agent signee, and pair him up with an early-to-mid-round draft pick like Auburn’s Montravius Adams, Washington’s Elijah Qualls, Clemson’s Carlos Watkins or Alabama’s Dalvin Tomlinson.

Each fits the interior bully mold, and are all wired to stop the run, which is an area this defense needs to improve.

In this potential route, Saleh could go with a 50-50 or so split with Mitchell and a rookie defensive tackle. It’d be a low-cost way to remedy the position—while being able to spend high draft capital and money elsewhere—and it is an area that really could emerge as better than serviceable. It also preserves a slightly injury-prone Mitchell, and provides a safety net in case he’s ever unavailable.

Step 2: Find a three-down EDGE

Route 1: Invest heavy

The Melvin Ingram dream was short-lived as the Chargers announced the application of the franchise tag on Monday. He would’ve been a versatile piece for the 49ers in their transition. But, nevertheless, a world of possibilities remain.

High first-round picks would be considered investing heavy here, and with the way the class is set up, and where the 49ers pick, they could land what turns out to be their best overall player on the defensive line. I say that because I, as well as most of the draft community, have a pretty high opinion of Myles Garrett, Jonathan Allen, Solomon Thomas and Derek Barnett.

These four top prospects are all in play to man the edge or “LEO” for the 49ers. Let’s picture what the final product could look like after free agency and a first-round investment . . .

Combo #1:

Garrett (LEO)-Poe or B. Williams (DT/NT)-Buckner (DT)-Armstead (LDE)

*This is a group the 49ers could go hard after, and it would be the ultimate of end results. Poe and/or Williams could get free from their respective teams, as we mentioned, and the Browns could still take Jonathan Allen at No. 1 or even go quarterback – or swap picks with the 49ers if John Lynch wants Garrett bad enough. You just can’t rule Garrett out until he’s officially drafted. This D-line, if assembled, would be the equivalent of the Dallas O-line, from an emergence, youth and impact standpoint.

Combo #2/3:

Allen or Thomas (LEO)-Poe or B. Williams (DT/NT)-Buckner (DT)-Armstead (LDE)

*If the 49ers intend to draft Jonathan Allen, or Solomon Thomas for that matter, either could theoretically play inside next to Buckner, allowing them to bypass an expensive free-agent NT. That's one luxury their versatility provides. But both Allen and Thomas also fit well in the LEO role, and have the dexterity to play all over the line, in fact. And while this line combo would have a ton of horsepower and maybe not enough speed, that model hasn’t hampered Seattle too much.

Combo #4:

Barnett (LEO)-Poe or B. Williams (DT/NT)-Buckner (DT)-Armstead (LDE)

*Barnett appears to be the alpha EDGE the 49ers have been without since Aldon Smith’s last productive season in 2012. The dominant genes and track record of production are both there with Barnett, as he racked up 32 sacks and 52 tackles for loss over the past three seasons for the Vols. He’d play well off the rest of this unit and has the potential to turn in 10-plus sack seasons.

Combo #5:

Garrett (LEO)-Adams or Qualls or Watkins or Tomlinson (DT/NT)-Buckner (DT)-Armstead (LDE)

Combo #6/7:

Allen or Thomas (LEO)-Adams or Qualls or Watkins or Tomlinson (DT/NT)-Buckner (DT)-Armstead (LDE)

Combo #8:

Barnett (LEO)-Adams or Qualls or Watkins or Tomlinson (DT/NT)-Buckner (DT)-Armstead (LDE)

Route 2: Seek value

There’s a good deal of intriguing fringe first-round and mid-round edge talent in 2017. Charles Harris of Missouri, Taco Charlton of Michigan, Tim Williams of Alabama and Ejuan Price of Pitt are a handful of naturals that come to mind.

These four will serve as the plug-in examples here – essentially capable 43 pass rushers the 49ers wouldn’t have to select at No. 2 overall, but ones that can still be impact starters from the LEO position . . .

Combo #1:

Harris (LEO)-Poe or B. Williams (DT/NT)-Buckner (DT)-Armstead (LDE)

*Harris could most definitely be an option for the 49ers at No. 34. He’s a monster of a defensive end, coming from Mizzou’s 43. Based off his pro-readiness and scheme familiarity, his transition would be more seamless. While providing more of a balanced edge presence, Harris, with his motor, explosiveness and nifty inside spin move, could handle the duties of being the team’s primary source of pass rush.

Combo #2:

Charlton (LEO)-Poe or B. Williams (DT/NT)-Buckner (DT)-Armstead (LDE)

*Charlton could be a trade-up option at the end of the first round or perhaps be the early Day 2 pick for San Francisco. Coming off a 10-sack senior season for Michigan, he’d plug in as the starting right defensive end, providing a lengthy high-caliber pass rusher. And playing off either Poe or Williams, he’d draw a lot of 1-on-1s and free rushes. Even with Mitchell or Purcell on the field, Charlton is capable of dominating.

Combo #3:

T. Williams (LEO)-Poe or B. Williams (DT/NT)-Buckner (DT)-Armstead (LDE)

*The 49ers could get great value with Tim Williams, who is among the elite EDGE prospects in this class. The back-to-back double-digit sack artist from Alabama could be a trade-up candidate for San Francisco, as he could perhaps be had in the back end of the first round. Williams would bring explosive edge rush and tenacity to this line group. He’d also bring a bit of the versatility Ingram would’ve offered, in that he’d also be able to play standup LB.

Combo #4:

Price (LEO)-Poe or B. Williams (DT/NT)-Buckner (DT)-Armstead (LDE)

*Price is a very fun player. At 6-foot, he's learned to play the leverage game. Price consistently bends and drives to the quarterback, attacks from all over and generally competes hard. And with his stature, Price has drawn comparisons to James Harrison and Elvis Dumervil, in that he wins similarly. But can he hold up as a starter at the next level? Can he handle the run? Others have, but we’ll see with him. And if he does, he can be a dynamic edge player in the NFL.

Combo #5:

Harris (LEO)-Adams or Qualls or Watkins or Tomlinson (DT/NT)-Buckner (DT)-Armstead (LDE)

Combo #6:

Charlton (LEO)-Adams or Qualls or Watkins or Tomlinson (DT/NT)-Buckner (DT)-Armstead (LDE)

Combo #7:

T. Williams (LEO)-Adams or Qualls or Watkins or Tomlinson (DT/NT)-Buckner (DT)-Armstead (LDE)

Combo #8:

Price (LEO)-Adams or Qualls or Watkins or Tomlinson (DT/NT)-Buckner (DT)-Armstead (LDE)


The reconstruction of the D-line is a big deal this year. It’s a position group in flux, a lot has been invested there from the previous regime, there’s several undefined players in-house, and there’s a great deal of available line talent out there, as well as draft picks and money to acquire said talent.

The free agents for this rebuild example are locked in, seeing as how Poe and Williams are the two elites available, while the DT class beneath them is soft. All the EDGE talent was quickly franchise tagged, as well. But for the draft, you can envision the prospects listed above for the 49ers or sub them out with your own crush.

We used 14 different players - just two veteran free agents - to generate a host of options that could complete the formation of this line.

This is more of a rough draft or outline of what the defensive line could look like after it’s tended to this offseason.

With so many needs, a down-the-middle approach could be what they opt to do. For instance, a combination of Brandon Williams (invest heavy) and Charles Harris (seek value) may work, two players that could come in right away and be quality starters. The 49ers could even decide to bring in an entire section of the Alabama line altogether, grabbing Dalvin Tomlinson as the interior tackle and either Jonathan Allen or Tim Williams for the edge.

The possibilities are endless when it comes to capping off this new line. It’s all about the combo they choose and where they ultimately decide to play everyone. When the chips fall, which route will they decide to go?

One thing is certain, there’s a ton of opportunity this offseason for new general manager John Lynch and the 49ers to quickly make this unit one of the NFL’s best. Given what they have in place, what they need and the fully stocked 2017 market, they have a chance to lay the foundation for the next generation of this defense.

Media courtesy Baltimore Beatdown, Reddit, Sports Mockery, Pro Football Focus,

#mylesgarrett #dontaripoe #nfldraft #2017nfldraft #nfl #nflfreeagency #49ers #sanfrancisco49ers #ejuanprice #timwilliams #solomonthomas


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