Film breakdown of Everson Griffin, Harrison Smith, and the Vikings’ defense

After taking a look at Kirk Cousins, Dalvin Cook and the Minnesota Vikings’ offense, it’s time to shift gears toward their daunting defense, led by head coach Mike Zimmer. The 49ers are opening on the road against the NFL’s best defense, who replaced one starter since last season. The one starter they added — Pro-Bowl defensive tackle Sheldon Richardson.

Head coach Kyle Shanahan and quarterback Jimmy Garoppolo will have their hands full, as they look to come away with a season-opening victory. When asked about the different challenges that the Vikings’ defense present during Wednesday’s press conference, here’s what Shanahan had to say.

“A lot. They’re a very talented defense in terms of, I think if anyone said their best talent was their D-Line or their linebackers or their secondary, I’d say whichever one you said is right. You could argue any of those three. They’ve got a lot of talent there with high draft picks, guys who have made second contracts. It’s a very good scheme, too. With what [Minnesota Vikings defensive coordinator] George [Edwards] and [Minnesota Vikings head coach] Mike [Zimmer] have done over the years, it’s extremely sound. Then, you’ve got 11 guys that have been playing together for about four years. I know they added [Minnesota Vikings DT] Sheldon [Richardson] as a three technique, but the last 10 guys have been there for a while and that continuity of good talent with a good scheme is why their numbers were as good as anyone’s last year in pretty much every category.”

Minnesota’s defense has multiple advantages — the majority of their premier talent has spent a few seasons together and they have superstars sprinkled at every level of the defense. Zimmer can lean on lineman Everson Griffen along the defensive front, linebacker Eric Kendricks in the middle of the field, cornerback Trae Waynes on the outside, and safety Harrison Smith in the back end. Here are some things that 49ers’ fans will need to know ahead of Sunday’s opener.

Vikings’ dominant defensive front

Minnesota doesn’t have the traditional pass rusher — there’s no Khalil Mack, Von Miller or Melvin Ingram just flying off the edge, looking to take the opposing quarterback’s head off. The Vikings line up stout interior defenders across the defensive front and try to out-muscle your offensive line.

Earlier in the preseason against the Jaguars, defensive ends Danielle Hunter and Brian Robison come flying off the edge, sacking quarterback Blake Bortles in the red zone. Bortles had no chance to save the play, as Hunter knocks him down immediately after the snap.

Last season, the Vikings had at least four different players with at least 3.5 sacks, with Griffin leading the way with 13.5 sacks. Defensive lineman Linval Joseph, along with Griffin, Hunter and Robison are the four returnees that the 49ers will need to pay attention to. Seems lethal, doesn’t it? Well, the Vikings were not complacent and added Pro-Bowler Richardson to the mix — who brings 19 career sacks to the table.

Last season, Minnesota’s run defense ranked No. 5 in the NFL, giving up 3.7 yards per rushing attempt. In theory, that number should only improve with the addition of Richardson, who’s a premier interior run defender. So far, through four preseason games, the Vikings rushing defense seems to be playing as well as most expected.

In this play against the Jaguars, running back Leonard Fournette had no where to go, as Robison pushes the Jaguars’ right tackle back. As soon as the ex-LSU running back starts to go East-West, instead of North-South, the rest of the Vikings’ defense is quick to collapse and finish off the play.

Here’s another instance of the Vikings’ “flock to the ball” run defense. On this toss play to Fournette, Joseph pushes the Jaguars’ lineman up the field, Hunter holds his block, while linebacker Anthony Barr is quick to get to Fournette.

Fournette did not have a chance to get out to the edge and turn up field. As long as the running backs aren’t running North-South, they won’t have a chance against the Vikings’ defense.

The key to Garoppolo’s success will depend heavily on the time his offensive line gives him. Linemen Joe Staley, Weston Richburg and Mike McGlinchey should be ready to go, but the biggest question mark is at right guard, where it seems like Mike Person has earned the start over Josh Garnett.

The 49ers’ running backs, Alfred Morris and Matt Breida, cannot make too many moves in the backfield. It’s going to have to be a “one cut and go” kind of afternoon, otherwise the second level of the Vikings’ defense will be all over the 49ers’ running backs.

Minnesota’s strong secondary

In 2017, the Vikings’ pass defense perfectly complemented the rest of the team, ranking No. 1 in opponent’s passing yards per game and No. 2 in opponent’s passing touchdowns per game.

The leader of that group isn’t necessarily a corner, but it’s superstar safety Harrison Smith, who finished last season with a team-high five interceptions (they had 14 as a team). Pair that with fellow All-Pro corner Xavier Rhodes, the Vikings have themselves a duo that most teams don’t. Add to that mix, young corners Trae Waynes and Mackensie Alexander and it’s shaping up to be a difficult game for the 49ers’ receivers.

Against the Jaguars, Smith was already in regular season form, picking off Bortles early in the first quarter. The Jaguars’ quarterback stared the wideout during the entire play, which Smith read beautifully and was in prime position to intercept the ball.

Bortles had another chance to be intercepted, as wideout Dede Westbrook slipped on the route, allowing the Vikings’ corner to step in and tip the pass. It seems like the Vikings’ secondary is always around the ball and any little mistake can be flipped into a back-breaking turnover.

While Garoppolo’s interception rate has often been wrongfully criticized since he joined the 49ers, he must be extra careful with the ball on Sunday. There’s no time for the 49ers’ signal caller to make a mental mistake, like Bortles does here because the Vikings’ secondary will make San Francisco pay.

The one area that the 49ers can certainly exploit the Vikings’ defense is short passes to the running backs out of the backfield. That’s probably where running back Jerick McKinnon’s presence will be most missed. McKinnon’s ability to make plays while catching balls out of the backfield might be his strongest suit.

Watching a few of the Vikings’ preseason games, this was a play that offenses often used against them to beat that daunting defense. With five rushers far up the field and the secondary far down the field, it left the middle open for Fournette to exploit.

Shanahan will have his hands full on Sunday afternoon in the season opener, with this defense, who should be even better at home in Minneapolis. The 49ers will have some question marks at their right guard and running back positions. Receivers Pierre Garçon and Marquise Goodwin will have to be effective early, to help take the pressure off of rookies Dante Pettis and Richie James Jr. in their first game.

Garoppolo will need to protect the ball, avoid interceptions, and take advantage of the short passing game. Vikings cornerback Xavier Rhodes has been ruled out for Sunday, while Mackensie Alexander is listed as doubtful. Their absences would put rookie corner Mike Hughes in the spotlight — and someone to exploit early in the game.