Facing the Cardinals offense on a short week was always going to be a difficult task for the 49ers. A lot of what Arizona does is relatively unique, notably their use of 10 personnel and spread formations. Furthermore, I am a firm believer that as a play-caller, Kliff Kingsbury is the second-best in the NFC West.

Unsurprisingly, therefore, the 49ers had their struggles in their first clash of the season with Kingsbury’s Cardinals. Kingsbury schemed up some superb plays against the 49ers mostly single high looks (over 80% single high coverage vs. the Cardinals), whilst the 49ers were themselves somewhat undisciplined and indecisive.

Perhaps they did not expect such a stern test; there was certainly an element of panic in some of their play and play-calling, especially once the Cardinals went up-tempo in the second half. Most notably, the 49ers were caught out on occasion against fire zone blitzes.

Nevertheless, the match was an important lesson for the team, and the offense also showed it could win games when the defense was not firing. The defense will have plenty to mull over as they prepare for Russell Wilson, but their clash with the Cardinals will have been good preparation for that, as well as giving them a useful insight before their rematch on November 17th. They will need to be much more disciplined and decisive against the Seahawks and may need to mix up their coverages between two high and single high coverages more.

The Film

On the first play of the game, Kingsbury attacked Fred Warner in the run game. Warner has been phenomenal against the pass this season but has struggled at times with hesitancy against the run. Kingsbury knew that by aligning two tight-ends to the same side on the LOS and a receiver in a narrow split, Warner would be in the backside B gap. Kwon Alexander is the base SAM, and Jaquiski Tartt also tends to align to the strong side.

Kingsbury called for a power run, with right guard (previously opposite Warner) and a tight-end lead blocking. He was able to make the front-side C gap enormous by blocking down on Buckner.

When Warner saw the guard pull, he needed to trigger and follow him. However, he hesitated, perhaps hoping to ensure there was no cut-back through the backside A gap. Alexander correctly attacked the pulling guard’s outside shoulder, whilst Tartt held his gap well with Emmanuel Moseley filling outside him. Warner, however, was not there fill inside the guard.

This hesitancy showed up on a couple more occasions. Given the Seahawks’ commitment to the run, the 49ers will have to be considerably more decisive on Sunday, or they will risk being drawn into an unwanted trench-based war.

Cover 3 is most vulnerable down the seams, which Kingsbury targeted on this play. Having a quarterback like Kyler Murray allows you to do many things... a play-action QB lead draw is one of the more exotic. Here, the 49ers were playing Cover 3 but were pattern-matching. In this instance, Tartt was playing soft sky coverage, which means he matches vertical routes from the number two receiver to his side. In this play, that is Maxx Williams in the backfield. Concurrently, Jimmie Ward plays a lean post technique, leaning to the left side to offer help over that side. Against certain concepts, it plays out like quarters.

Kingsbury’s play-call is superb and surely, at least in part, inspired by Kyle Shanahan. He puts Tartt in conflict, who has a run fit and seam coverage responsibility. Williams shapes to be Murray’s lead blocker on the QB draw play. When Murray pretends to run, Tartt stops his feet, momentarily preparing to engage Williams. Murray pops back up, and Williams darts past up the seam. The curl to the same side keeps Moseley well away from the play. Though the pass was incomplete, this design was a further warning that Kingsbury could scheme the 49ers up.

Continuing his threatening first drive, Kingsbury called a curl-flats concept to attack the 49ers’ coverage rules further and keep his offense moving. Once again, he attacked Tartt’s soft-sky responsibilities, putting him in conflict. On this occasion, he threatens to send a receiver down the seam or on a quick-curl whilst simultaneous running Williams into the flats. Having two routes running into the same player’s zone is an ideal situation for an offense. Williams was able to break off a significant yard after the catch and get another first down.

The 49ers did adjust after this. They told their flats players to chase the flats route aggressively whilst the cornerback had to sit on the curl with inside help from the hook. Nonetheless, the Cardinals had a lot of success with this concept throughout the game, including at the start of the second half, when Fitzgerald broke off a big catch-and-run running the curl. It was surprising that the 49ers did not come into this clash with a clearer plan from the start to handle curl-flats.

The Cardinals also had success on read-option plays. This is another area the 49ers will need to clean up before they meet the Seahawks.

The 49ers have been asking their back-side linebacker to have two gaps on occasion essentially. In addition to having the back-side B gap, they are asked to fall back on QB keepers or jet action. They are helped in this endeavour by the back-side end squeezing inside, compressing the B gap.

On this design, Kingsbury once again ensured he could attack Warner. With the 49ers in nickel against his 11 personnel, he knew Warner would be aligned to the passing strength (and thus the nickel corner).

Bosa was the read on the play. As soon as he crashed (which would have been expected), Murray pulled the ball. Warner was unblocked, but Kingsbury trusted Warner’s decision making and Murray’s speed would take him out of the play anyway. He guessed correctly.

Furthermore, by packaging the read-option with a screen to the back-side, Kingsbury created a vast amount of space for Murray to run into.

The 49ers got caught in fire zone blitzes on a few occasions by the Cardinals, when it seemed Robert Saleh was attempting to force the issue a little too much.

On this play, Saleh has called a fire-zone blitz. It plays out 3 under, 3 over. K’waun Williams and Warner blitz. This leaves Ward and Bosa as alley players whilst Alexander is in the hole.

Kingsbury’s screen call likely would have given the 49ers problems had they been running their normal cover 3. The two verts & flat combo would have left the MIKE isolated on the back, with four receivers on the strong side of the formation. The Cardinals would have had a four on four (plus one with late help from Tartt).

Once Saleh blitzed, the Cardinals actually had a four on two, albeit with late help from Alexander and Tartt. Resultantly, Alexander panicked slightly. He knew that the Cardinals were in an immensely favourable situation and attempted to make the play himself, under-cutting the block. This was admirable but undisciplined and gave up the edge. A similar play happened to Tartt shortly afterwards.

The Cardinals’ third-quarter touchdown was a masterful design by their coach that exploited the 49ers’ tendencies. It is a perfect play to finish the main portion of this article.

The 49ers were playing cover 3 in the red zone. Initially, they were playing with a strong side safety rotation to the trips side (a RITA rotation here - Right Inside rotation). However, Kingsbury knew that the jet motion would bring Tartt down as the force player and make Ward rotate back into the deep centre position.

Furthermore, he likely suspected that Tartt would have soft-sky responsibility again and have to match the number two receiver vertical. Kingsbury let his number two receiver block initially, to sell play-action (baiting Tartt up), before releasing vertically and running a deep corner route.

Kingsbury also knew that with such a rotation, Alexander would be the weak hook defender. This meant he had to play a robot technique and look to get underneath crossing routes coming from the other side. Ward, who was having to rotate back into the deep-centre field, would need to get over the top of them. Thus, Kingsbury ran hard play-action to the left to create misdirection and confusion for Alexander and Ward, whilst sending a dangerous deep crossing route back across the formation that both players needed to bracket.

Additionally, Kingsbury allowed the jet action to stay in the flats. This held Sherman down slightly because Sherman knew Tartt had to carry the deep corner route.

Resultantly, instead of the play being on the trips side, where the 49ers had initially had most of their players, Kingsbury had schemed up a play to get three receivers on the other side of the formation. With Tartt just about staying with the corner and Sherman occupied by the player in the flats, the deep overcame open. Ward lacked underneath help from Alexander and was outrun across the field after taking a false step towards the run.

A genius play design and call.

The loss of Kwon Alexander

What does the loss of Kwon Alexander mean for this defense? The team asked a lot of Alexander; I mentioned a few weeks ago that they had found a box safety skillset in a linebacker’s body. Robert Saleh gave him the freedom to run sideline to sideline, and his coverage ability in intermediate areas and against tight-ends or running backs was formidable. Dre Greenlaw will replace him and looks to be a talented player.

On Thursday, Greenlaw stepped into Alexander’s base SAM, nickel WILL role, and played well. He has generally been the base WILL linebacker and has shown his speed and aggression against the run to good effect. Furthermore, he has shown some ability to play the required robot technique and find crossers behind him. However, he is not as good in coverage as Alexander, and this is where we may see the biggest drop-off. How quickly will zone windows close, forcing quarterbacks off-targets and into hitching with Greenlaw more in the mix? That has been crucial to the 49ers’ pass rush success.

We may see the 49ers tweak things a little as well. I expect Greenlaw won’t have to cover the areas and players Alexander did quite so often, especially on later downs. Those responsibilities would fall on a defensive back.

Additionally, the 49ers may ask more of Jimmie Ward and particularly Jaquiski Tartt to play as the weak hook player looking for deep over routes and coming up aggressively against the run. We may also see the 49ers play more quarters with a safety playing aggressive sky coverage behind Greenlaw, covering for his aggressive tendencies against the run and protecting against routes behind him. We could also see some more press coverage to Greenlaw’s side, as the 49ers look to delay the releases of receivers into his area somewhat.