Why Kyle Shanahan and the 49ers’ offense will shred the Seahawks’ pass defense

Most of the focus on the 49ers-Seahawks’ showdown has been on quarterback Russell Wilson and the Seahawks’ high-powered offense facing off against the 49ers’ vaunted defense. Meanwhile, lost in the shuffle is the other key matchup in this game — a Kyle Shanahan led-offense dueling against Pete Carroll’s defense.

Why does the national media continue to push the false narrative that the 49ers are a defensive led team that only has a complementary offense? San Francisco’s offense is better than most think, and it’s going to be on full display when it shreds Seattle’s 27th-ranked defense on Monday.

Through nine weeks, Shanahan’s group has been going quietly under the radar. But here is where they rank in some key areas:

Total Yards per game: 390.3 (8th)

Rushing Yards per game: 171.1 (2nd)

Points per game: 29.4 (3rd)

Average Scoring Margin: 16.6 (2nd)

Offensive DVOA: 5.5 percent (12th)

The other false theme that continues to be spread is that quarterback Jimmy Garoppolo has been nothing but a game manager for a team that has a dominant rushing attack and a stingy defense. But again, here are some key statistics that show that Garoppolo’s quietly been really effective, as he continues to get himself back into rhythm after tearing his ACL last season.

Completion Percentage: 70.8 (3rd)

Yards per Attempt: 8.0 (7th)

Quarterback Rating (QBR): 69.8 (6th)

Shanahan and the 49ers have done an exceptional job easing Garoppolo back into the fold after recovering from an ACL injury. The team has leaned heavily on the shoulders of running backs Tevin Coleman and Matt Breida while letting the defense come up with big stop after big stop. But the first sign of Garoppolo’s control of this offense came this past Thursday against Arizona.

Garoppolo finished the game completing 28-of-37 passes for 317 yards and four touchdowns, including no interceptions. The 49ers’ franchise quarterback made key throw after key throw down the stretch, sealing the deal for the 49ers. San Francisco will need another vintage Garoppolo performance on Monday, and I expect that he’ll deliver just that against a shaky Seattle secondary.

Before we get to some clips breaking down Seattle’s leaky pass defense, here are some key statistics that should provide some excitement for 49ers’ fans — even if tight end George Kittle is not suiting up.

Opponents’ points per game: 25.6 (22nd)

Opponents’ passing yards per game: 278.1 (28th)

Opponents’ team completion percentage: 64.7 (17th)

Opponents’ yards per completion: 11.2 (23rd)

Opponents’ average passer rating: 89.6 (14th)

Sack percentage: 4.16 percent (29th)

To put all of these statistics into simpler terms, Seattle’s defense gives up a lot of points, yards through the air, and the opponents’ quarterbacks are completing a lot of passes due to having a lot of time in the pocket.

Per Pro Football Focus, Seahawks’ starting corners are going to be attacked all night. Corner Shaquill Griffin is their best secondary player, and he’s graded out at 73.4. The other two corners, Tre Flowers and Jamar Taylor, grade out less than 50 — which should worry Seahawks’ fans. They will also try to incorporate new safety Quandre Diggs into the mix, which can’t help matters.

It’s a formula that Garoppolo and the offense should be excited about, considering they will likely have tackles Joe Staley and Mike McGlinchey back, along with fullback Kyle Juszczyk after missing the last few games with injuries.

In this first play, the Seahawks are in a Cover-3 defense, with the cornerbacks and single-high safety playing in a zone defense. Buccaneers’ wideout Mike Evans can run a post route right through the seam of the defense and have a huge gain. Seattle’s pass defense plays it too soft at the line of scrimmage, and the 49ers’ receivers will be able to feast if Seattle plays like this on Monday.

Here’s a sweet design from head coach Bruce Arians and offensive coordinator Byron Leftwich. They send Perriman on a wheel route and fake a screen to wideout Chris Godwin. With the Seahawks in man coverage, the defensive back gets lost behind the receiver, and Winston can deliver a great ball.

We know there’s nobody better than Shanahan at scheming his receivers open, so if the Seahawks’ defensive backs continue to make these mistakes, they’re going to pay on Monday night.

Now, against the Ravens, the Seahawks are in a Cover-3 in the opening drive. Ravens’ wideout Miles Boykin blows by the single-high safety (who’s supposed to be the last line of defense). Quarterback Lamar Jackson delivers a good ball, and it’s a chunk play.

The 49ers don’t normally take deep shots, but they use the play-action to catch defenders off. If the safeties and corners fall for the fake, there could be a lot of giant; chunk plays on Monday.

Here’s where having Kittle will be huge against the Seahawks because he’s going to present a matchup nightmare against their linebackers. Against the Ravens, tight end Mark Andrews is matched up against linebacker K.J. Wright and blows by him on the route and makes a huge catch.

Imagine Kittle in Andrew’s spot on Monday night. Oooooowieee!

The 49ers’ passing game finally woke up against the Cardinals and it was the right time for it. Playing a dominant offense, the 49ers might be required to put up a lot of points and they may just do it — thanks to a shaky Seattle pass defense.