• Travis Rapp

Defensive Cornerstones the 49ers Can Build Around

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The 2020 San Francisco 49ers defense was somewhat enigmatic. To say they were hit with injuries is an understatement, as linebacker Fred Warner and defensive lineman Arik Armstead were the only two defensive players to play in and start all 16 games. They were without their best pass rusher and defensive player Nick Bosa since Week 2, and their second-best pass rusher, Dee Ford, for all but one game (their first game). Future Hall of Fame cornerback Richard Sherman played in five games. With all of these injuries it was impressive that defensive coordinator Robert Saleh was able to put a defense on the field week in and week out who still competed and punished opponents.

At the end of the season the team ranked fifth in total yards against, fourth in passing yards given up, seventh in rushing yards given up, had the third lowest third down conversion rate, but were 17th in points against, 23rd in turnover rates, 22nd in sacks, and 26th in quarterback knockdown percentage –all while having the fewest missed tackles in the league.

Enigmatic, indeed.

Looking at these team statistics tells us that they played sound defensive football, but in the end really missed the individual players who could make that drive-ending sack or create that pass breakup or interception in the red zone to keep a team from scoring. The points against statistic was also hurt by the offense’s penchant for turning the ball over on their own side of the field, just like at the end of the Week 17 game against the Seattle Seahawks when C.J. Beathard fumbled the ball at the 49ers 17-yard line, setting the defense’s backs against the wall.

So if the scheme is sound, which players showed that they are worth being built around moving into the 2021 season? That’s the question we’ll answer here today. With a decrease in the salary cap for the first time since it was instituted in 1994, the 49ers, like the other 31 NFL franchises will need to self-scout themselves even better and identify those players they wish to hold on to and build their team’s core around. I’ve identified two players at each level of the defense the team needs to do just that with.

Defensive Linemen:

After his breakout season during the team’s run to Super Bowl LIV, Arik Armstead was once again asked to play out of position and put up pedestrian numbers. This was mostly due to other players’ injuries. One of those players who were injured was all-world talent Nick Bosa. In his nearly five quarters of play this season Bosa had six tackles and a forced fumble. Going into the season, Bosa was seen as a possible Defensive Player of the Year candidate, and going into 2021, he should be seen as that again, and a Comeback Player of the Year candidate. By all accounts, his rehab has gone well and he is on track to be 100 percent by the start of next season. He’ll have two more seasons on his rookie contract, before his fifth year option is picked up or he is signed long term. Bosa is the type of player you never let leave the building.

The second defensive lineman on the roster to build around is defensive tackle Javon Kinlaw. A physical beast at 6’5” and 320 pounds, the 49ers picked a great player to replace DeForest Buckner on the interior of the defensive line. He did not put up the type of number fans were used to Buckner putting up, but in 14 games he did have 1½ sacks, 33 tackles (3 for a loss of yardage), and showed his athletic ability on a mid-season pick six. The sky is the limit for Kinlaw, and the team will enjoy having him on the rookie contract for three more seasons before picking up his fifth-year option or signing him long term.

With a healthy Bosa and Kinlaw, the defensive line will be able to flourish again by being able to put Armstead inside next to Kinlaw and allow Bosa and whoever starts as the opposite defensive end (Kerry Hyder?) and watching them all meet in the middle of the opposing team’s pocket.


For many years the 49ers fan base was lucky enough to watch teammates Patrick Willis and NaVorro Bowman roam sideline to sideline as the best linebacker duo in the NFL. Sometimes, history has a way of repeating itself. Fred Warner has proven he deserves to be in the discussion as LB1 in the entire league, while running mate Dre Greenlaw will continue to push him to prove that he is just the LB1 for the 49ers. Warner, a first year captain, made the Pro Bowl this season with 125 tackles, 1 sack, 1 forced fumble, 2 fumble recoveries, and two interceptions. Warner is the heart and soul of this defense, and will get paid this offseason like he is the heart and soul of the defense, even if Bosa might claim the top defensive player award.

Greenlaw was second on the team in tackles with 86, while playing in only thirteen games. He also recorded one sack, seven tackles for loss, and had a pass defended. Greenlaw, the man of goal line stops and fourth quarter interceptions, had a bit of a down year, for him. Nagging injuries and missing three games lowered his statistics a bit, but his ability to track ball carriers and defend tight ends and running backs in pass coverage –much like Warner, makes him an invaluable member of the defense. He is also the reason the team felt comfortable trading away Kwon Alexander mid-season; Greenlaw had simply been outplaying him since his rookie season. Greenlaw has two years left on his rookie contract before he will be looking for a big payday. That will be an important offseason for the 49ers, as both Bosa and Greenlaw will be looking for long-term contracts.


During an offseason in which nearly every single starting defensive back is slated for free agency, this will be the hardest place to create consistency. The two players they need to keep in the fold and build around have expiring contracts. After several seasons of being hit hard by the injury bug, all of Jason Verrett’s hard rehab work paid off. People were reminded why he was once considered a top five cornerback in the league. PFF graded him out at a 76.1 coverage grade (14th best cornerback in the NFL) and an plus he showed he wasn’t scared to mix it up by being the fourth top tackler on the team with 60 tackles in his thirteen games. That combination of his game gave him a 77.6 PFF grade, making him the ninth best cornerback in the NFL, according to PFF. Verrett was able to do this almost all season, regardless of who was starting on the opposite side of the field. He was also a recipient of multiple team awards, as voted on by the players and coaches.

The other defensive back who the team needs to bring back and build around is nickelback K’Waun Williams. Thought of as one of the top nickel cornerbacks in the league, Williams’s value for the team has increased as the receiving corps of the NFC West has continued to improve. With more teams going with three-wide sets, Williams’s ability to shut down the slot receiver has become rather invaluable. Injuries only allowed him to play in eight games this past season, which might actually help the team keep him in Santa Clara. With safety Jimmie Ward as the only defensive back with significant playing time under contract, what the secondary is going to look like next year could be anyone’s guess. Bringing back Verrett and Williams would allow the team to target a CB in the draft to compete against Emmanuel Moseley (an ERFA who will probably be re-signed) to start opposite Verrett. Having Williams back at nickel cornerback would allow Ward to focus on his job as safety and not force him to cover slot receivers.


In all honesty, the defense should be one of the best in the league next year as long as the scheme stays similar and the team is able to promote or bring in someone who can take over as defensive coordinator once Saleh is hired elsewhere. The main takeaway is, that even with all of the free agents the team has this coming off-season, they have core players at every level they can build around to keep this dominant defense deflating the rest of the league.

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