Key Factors to Watch When the 49ers Face the Cardinals

The Niners get their first pop quiz of the season as the Arizona Cardinals come to town. Although they have looked bad in the past two weeks, this Cardinals team has an offense that can come alive in an instant, so what do the Niners need to do to secure the win?

Sep 29, 2024; Santa Clara, California, USA; San Francisco 49ers quarterback Brock Purdy (13) throws a pass against the New England Patriots during the third quarter at Levi's Stadium. Mandatory Credit: Sergio Estrada-Imagn Images / Sergio Estrada-Imagn Images

The Niners have gotten back to their old ways, after beating the Patriots 30-13 they now face a familiar foe in the Arizona Cardinals. The Cardinals are coming off a pair of losses to the Lions and Commanders, two very competitive teams. But they did win against the Rams, giving them confidence against this Niners team. So who/what are the key factors for the Niners to get a streak going?

OFFENSE

1. Brock Purdy

I'm assuming Brock Purdy is hyped for this matchup. According to PFF the Arizona Cardinals rank 28th in Pass Coverage, near the bottom of the league. On top of that, they also rank 30th in Pass Rush and 32nd in opposing QB Completion Percentage at 78.6%. This is a terrible defense that won't be able to endure the variety of threats in the Niners pass game. Brock should be doing what Brock does best, smart QB play. I don't want to see deep balls that can turn into interceptions. Let's get back to the Kyle Shanahan ways, smart decisions for easy yards. The only real way the Cardinals can combat this would be by attacking Purdy's weakest PFF stat this season. The newly introduced and now personal favorite, Sideline-Passing Grade. This stat is curated to throws within two yards of the sideline. Purdy is currently ranked 19th with a 59.2 grade. He has completed 47.06% of his passes there with 87 yards. Compared to last year, he's fallen off. In 2023 Purdy was the best at those throws, he was ranked 1st with a 92.2 Sideline-Passing Grade with a 60% completion rate. Is he worse than last year? Yes, but let's not forget we have a tiny sample size. I'd expect it to get better as the year goes on. I'd expect the Cardinals to continue their high zone defense rates (70+%) and try to clog the middle of the field, giving Purdy the chance to bring up his Sideline-Passing Grade. Seems easy enough.

2. Jordan Mason

The Cardinals aren't as bad at stopping the run as they are at stopping the pass. This season the Cardinals rank 18th in Run Defense Grade at 59.9 (only 1.2 points off the 49ers). They can stop the ball, especially with Budda Baker running downhill. The key here is going to be how they can confuse this defense with the passing game. If they can threaten the defense with Brock Purdy's arm, Jordan Mason's legs can destroy them. So far this season, Jordan Mason has had more rushing attempts than anyone and with a 4.9 Yards Per Attempt, it makes sense why. The stat Mason isn't at the top in his longest rushes. Out of the top three rushing leaders, Mason has the lowest longest rush at 25 yards. This is the game where he gets the 30-50-yard rush he's been wanting.

3. Brandon Aiyuk

It feels like I'm starting to become a broken recored, I've said it over and over again and maybe I should stop. No. I won't. Brandon Aiyuk is due a big game here. Going against one of the worst CB groups in the league, he's got to get more than he has all year. Maybe this is me being bias because I have him in Fantasy Football, or maybe it's watching some bad balls thrown his way, who knows? What I do know is he's way better than 13 receptions for 167 yards. I'd anticipate it'll be passes in the numbers that get him the most targets, or maybe he gets a go route to secure some big yardage. However it's done doesn't matter. What matters is he shows that he's worth $30 million a year.

DEFENSE

4. Slowing Kyler Murray

Let's start this off with a little game, shall we? I'll give you stats for two Quarterbacks through 4 weeks and you get to determine who's playing better.
QB 1: 68.9 Completion %, 5 Pass TDs, 2 INT, 4 Fumbles, 104.9 Rating.

QB 2: 69.4 Completion %, 6 Pass TDs, 1 INT, 1 Fumble, 104.6 Rating.

So with that, how would you rank it? The majority of the stats are nearly identical, with a few outliers in TDs, INTs, and Fumbles. The reality might shock you. QB 1 is Brock Purdy and QB 2 is Kyler Murray. Now before you get mad at me, this is not me saying Kyler Murray is better than Brock Purdy, it's meant to show that Kyler is not a bad QB like narratives of the past have told. The fact that those stats are similar goes to show how good Kyler Murray is. Just like how Kyler Murray is tied with Purdy in Big Time Throws. This stat counts a pass with excellent ball location and timing, generally thrown further down the field and/or into a tighter window as a BTT. Currently, Brock and Kyler have 8 each, tied for second only behind Josh Allen's 10. So stop him from getting those throws up. Two high safeties at all times are the obvious solution. And the DLine should be effective at breaking the pocket down, which leads to the other issues of Kyler. His legs. Kyler scrambles often and efficiently, averaging 10.3 Yards per Rushing Attempt. With Fred Warner listed as questionable, who will deal with it if not him? De'Vondre Campbell doesn't have the speed to deal with Kyler in open space. Maybe a DLineman like Gross-Matos? But typing that almost made me hurl. Whoever it will be it'll be a tough matchup for them.

5. Getting better on 3rd Down Defense

The 49ers rank 26th in the NFL on 3rd down conversions allowed at 46%. And in case that isn't painful enough, they're last in 3rd-and-long conversions allowed at 50%. Last season they were ranked 27th with a percentage of 42.47%. Yes, it was similar last season, but with this recent Patriots game, it's somewhat inflated. If we don't account for that game, they drop to 30th with a 52.94% rate. That's abysmal. If we look at 2023, the lowest rate was 47.32%. This has to be figured out quickly and this game is an opportunity to make an effort at fixing it.

6. Slowing Tre McBride

Tre McBride is the only thing this Niners defense hasn't seen this season, a really good tight end, and with Fred Warner possibly not playing it gets scary. I'm having flashbacks to De'Vondre Campbell covering a TE in LA. Additionally, this will be McBride's first game back after suffering a concussion in Week 3. McBride has shown he has an amazing connection with Murray, and I'd bet it'll be shown in this game. Hopefully Sorensen will figure out a method to slow him down, but I'd guess he won't.

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