We’ll get to see Robert Saleh’s new defense compared to his old defense

The San Francisco 49ers host a Jacksonville Jaguars squad this week that is playing high quality pass defense. Their run defense is giving up 4.5 yards per carry, which is near the bottom of the league. But their pass defense ranks No. 1 and is at or near the top in most notable categories.

This weekend’s matchup is a big one for Jimmy Garoppolo and the 49ers offense, but the Jaguars defense offers another comparison. The 49ers are installing a defense that has been described as a Seahawks style defense. And yet, with the Seahawks on the down swing, the Jaguars are turning into the kind of model defense to which a team aspires.

And the coaching history involved makes this particularly interesting. Kyle Shanahan hired Jaguars linebackers coach Robert Saleh to be his defensive coordinator. Saleh joined the Jaguars when Gus Bradley left the Seattle Seahawks to take over as head coach. Saleh had been the Seahawks defensive quality control coach, learning with Bradley, Pete Carroll, and Dan Quinn.

Jaguars head coach Doug Marrone joined the Jaguars as offensive line coach in 2015. He was assistant head coach and when Bradley was fired in 2016, Marrone took over as interim head coach. Marrone was named head coach, and chatted with 49ers media on Wednesday. He was asked about Robert Saleh from their time together in Jacksonville.

“Obviously he’s a guy that has a ton of energy. he’s extremely, extremely bright. Very, very good with in the system — meaning that he knows the system inside and out. And then really from afar, what I see is it’s always difficult when you implement a new system, to get everything going. I don’t care whether it’s offense, defense, or special teams, when you’re with a team. And it looks like, the one thing they play extremely hard, they run around, they’re having fun, and they’re making plays. And they’re very good up front, they’re good in the back end, and I think obviously it’s the same thing, they’re hitting their stride on defense — now they’ve been in the system, they’ve been in the games, they’ve been through all the adjustments, and they’re really playing at a high level.”

The 49ers defense is a work in progress, and the 2018 offseason will play a critical role in the group taking the next step. There has been a quality talent infusion the past couple years, but 2018 is when they can add a couple key difference-makers that take this defense to a new level.

In the meantime, regardless of the outcome, Sunday will be an informative game for making some comparisons between the two defenses. The Jaguars have boosted their pass rush, and they have two of the best cornerbacks in the game. The 49ers have added young talent up front and in back, but are still at least a couple steps back of where the Jaguars reside. Sunday is not going to give us any final answers in this comparison, but it will offer a useful data point.