Previewing the San Francisco 49ers’ Starting Defensive Line

Football fans and film junkies often find themselves in separate camps on a variety of football-related issues.

• Should a team have a stronger pass game or a pounding ground attack?
• When building a roster, should a team start with skill players or linemen?
• How about drafting a punter in the fourth round of the draft?

During the offseason, one question I heard asked was if the 2019 San Francisco 49ers were a better defense due to its ball-hawking secondary or bludgeoning defensive line.

There's enough evidence to compare the 2018 49ers' defense with the 2019 version and craft a lengthy thesis supporting the secondary or the defensive linemen.

For me, the significant uptick in defensive line play places me squarely in the camp for a ferocious pass rush.

The 2018 49ers' dismal pass rush tallied a whole 275 quarterback pressures of any kind, resulting in a whopping two interceptions.

The 2019 49ers tallied 377 total pressures of any kind, including 66 sacks and 255 hurries, which resulted in 17 interceptions and home-field advantage during the playoffs.

Also consider the 49ers faced the Green Bay Packers twice last season, and, in both games, the 49ers' pass rush turned quarterback Aaron Rodgers into a crumbled biscuit.

For both games, the 49ers notched 10 sacks, three hits, and 24 hurries. Linebacker Fred Warner forced a fumble in Week 12, while defensive lineman Arik Armstead forced a fumble in the conference championship.

Though it's not always about sacks; I'd prefer a defensive line pound the fear of a 16-hour unhinged LSD journey into a quarterback's brain.

Here is a look at the projected first-team defensive line for the 2020 49ers.

Arik Armstead - Defensive Tackle

I refuse to hear certain blasphemies in the football world, and one of them is how Armstead's improved play was because he was in a contract year.

Gentle Reader, I hate to break the news to you, but every year is a contract year. The 49ers are not the local youth football team where everyone gets an equal share of playing time, with halftime orange slices and fetal spooning.

Armstead increased his numbers across the board in 2019, finishing with 13 sacks, 47 hurries, 38 tackles, and 40 stops. He earned an 89.6 grade from Pro Football Focus - 15.4 points better than 2018.

Armstead is also a player who can play anywhere on the defensive line. The bulk of his 909 snaps last year came from the LEO position, but he also took 165 snaps as an interior defensive lineman.

As an edge player, Armstead is effective even if not making a sack.

During the Week 3 win over Pittsburgh, Armstead controlled the end of the line of scrimmage, allowing linebacker Kwon Alexander to stalk running back James Conner and drop him for a loss. And it wasn't just an assist; Armstead pushed away from guard David DeCastro and was also in pursuit of Conner.


It's subtle moments like this during a football game that get overlooked. Production is more than a sack or a tackle.

With DeForest Buckner gone, the defensive line is Armstead's to lead, and I trust the men around him will follow.

Nick Bosa - Defensive End

Nick Bosa is a real-world example of an immediate impact athlete.

In 2018, the 49ers' defensive line had potential, but it missed a quality edge defender with speed, strength, and grit. Bosa brought those qualities to the front four in 2019, and it paid off in a trip to Super Bowl LIV, along with the AP Defensive Rookie of the Year hardware.

One of my favorite plays from Bosa was during his first game as a professional. Tampa Bay made the mistake of double-teaming each 49er defensive lineman but left tackle Donovan Smith alone in space with the rookie.


Defensive coordinator Robert Saleh put Bosa in a weak side wide-9 look, while defensive tackles Buckner and Armstead both aligned in a 3-technique. Defensive end Dee Ford was in a 9-technique over the 'U' receiver.


Tampa Bay was oblivious to Bosa's capabilities, and he nearly made them pay for the oversight. Bosa blew the doors off Smith, nearly sacked quarterback Jameis Winston for a loss, and showed the world what he could do if the opposition slept on him.

Javon Kinlaw - Defensive Tackle

Rookie defensive tackle Javon Kinlaw is the first player in the NFL to make me feel old. He was born on October 3, 1997, the same day the 1997 Turlock High Bulldogs beat rival Merced High on a warm San Joaquin Valley night.

As difficult as it was to say good-bye to Buckner, Lynch and Shanahan found the ideal replacement in Kinlaw. He is a gifted defensive tackle, playing just over 600 snaps between 2i and 4i-technique. In his last season at South Carolina, he had seven sacks and 13 run-stops to go along with 26 quarterback hurries.

Kinlaw might fit best as a 3-technique defensive tackle in the 49ers' scheme, as his quick lateral movement and size will cause centers and guards a lot of havoc.

Dee Ford - Defensive End

The combination of Bosa and veteran defensive end Dee Ford was an unstoppable force. Opposing offensive tackles could not stop the speed from both men, and asking a guard to help try and stop Ford would open up a gap for Armstead or Buckner.

Ford's most significant issue last year was dealing with lingering injuries, namely his hamstring strain in the Week 14 win over New Orleans. Ford also had problems with his knee and quadriceps throughout the 2019 season, resulting in him playing in approximately 27% of the 49ers' total defensive snaps.

One upside of zero organized team workouts during the offseason might have helped Ford's nagging problems fully heal. The 49ers need him to shoulder more of a load his season and play at least 40 or more snaps per game.

On Friday, I'll review the reserve defensive linemen, including a few players on the bubble to make the final roster.

All statistics courtesy of Pro Football Reference, unless noted.
All images courtesy of NFL.com.

• Bret Rumbeck
• Written by:
  Bret Rumbeck
  Bret Rumbeck has been writing about the 49ers since 2017 for 49ers Webzone and 49ers Hub. He is a Turlock, CA native, and has worked for two members of the US House of Representatives and one US Senator. When not breaking down game film, Bret spends his time seeking out various forms of heavy metal. Feel free to follow him or direct inquiries to @brumbeck.
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