Arizona Cardinals 33, San Francisco 49ers 21

Here are the top-graded players and biggest takeaways from Arizona’s 33-21 win over San Francisco:

Quarterback grade: Drew Stanton 43.8

While it’s hardly a ringing endorsement, the one positive thing I can say about Stanton’s performance was that he was making fairly good decisions with the ball. That’s about where the positives end though, as he was as erratic as you can be and still not have a ball picked off. His 39.3 completion percentage looks a little worse because of four drops, but those only bring his adjusted completion percentage up to a dismal 55.6. Throwing the ball down the field – one of the tenets of Bruce Arian’s offense – was certainly an adventure with Stanton at the helm. He completed two of 12 passes targeted over 10 yards down the field.

Top offensive grades:

LG Mike Iupati 84.2

RT D.J. Humphries 82.2

WR Larry Fitzgerald 81.8

C A.Q. Shipley 80.0

LT Jared Veldheer 79.0

Offensive line paves the way

Even with the 49ers knowing the Cardinals had to run the ball to generate consistent offense, the Arizona offensive line still manhandled San Francisco up front. The 11-play touchdown drive that ate up over six minutes of game clock in the fourth quarter was a masterpiece. Even with some backups in, not a single man upfront was losing his blocks. After running downhill blast and power plays for the first three quarters, the Cardinals went outside zone heavy on that drive and the 49ers couldn’t adjust. This unit was truly the difference in the game.

Top defensive grades:

DE Calais Campbell 84.3

CB Patrick Peterson 83.1

ILB Deone Bucannon 82.9

ILB Kevin Minter 81.8

OLB Markus Golden 79.9

Defense shuts down 49ers’ passing game

Patrick Peterson continued his stellar start to the season. Blaine Gabbert targeted him just once in his 47 snaps in coverage and did not allow a catch. Through five games, Peterson has allowed just nine catches for 89 yards on over 200 snaps in coverage. Oddly enough, one of the worst performances on defense was from Tyrann Mathieu as he moved back to more of a slot cornerback role. Mathieu allowed four catches for 47 yards and a touchdown, but also was called for holding and pass interference once each. In the front seven, Calais Campbell, Markus Golden and Alex Okafor had five total pressures each.

Quarterback grade: Blaine Gabbert 44.4

Blaine Gabbert started the night off decent enough, but his play dropped off as the game progressed. He completed just four of 11 passes targeted 10-plus yards downfield. Gabbert was pressured on 16 of 44 dropbacks. He managed to complete just two of six attempts for 13 yards and an interception for a 2.8 passer rating when pressured. The other ten plays resulted in seven sacks and three scrambles past the line of scrimmage. Even when Gabbert wasn’t pressured, he still chose to leave a clean pocket before necessary on several occasions. Sometimes he was able to pick up a first down with his feet, other times he broke his linemen’s leverage only to end up getting sacked. He was responsible for two sacks, and a third that was negated due to a defensive penalty.

Top offensive grades:

LT Joe Staley 78.3

WR Jeremy Kerley 78.1

RT Trenton Brown 74.4

RG Andrew Tiller 72.2

C Daniel Kilgore 69.7

Kerley shines while other skill players disappear

Jeremy Kerley was Gabbert’s go-to receiver Thursday night and it led to Kerley earning both his highest grade as a 49er, and his highest receiving grade since the 2013 season. Carlos Hyde also topped 100 offensive yards on his 27 touches, but the rest of the offensive skill players had little impact. WRs Quinton Patton, Torrey Smith and Rod Streater along with TEs Garrett Celek and Blake Bell ran a combined 136 pass routes in the game. Those five players combined for five catches for 24 yards and two drops with a long reception of nine yards.

Top defensive grades:

S Jaquiski Tartt 80.8

CB Tramaine Brock 80.8

CB Rashard Robinson 78.6

NT Mike Purcell 77.7

LB Nick Bellore 75.2

Run defense still a mess

The run defense was yet again an extreme issue and a week after posting the lowest run defense grade in the NFL, Arik Armstead will once again be in the running for that honor in Week 5. Instead of focusing on the easy target though, let’s highlight some positive performances from the defense. It’s still early, but I don’t believe it’s too early to see that the 49ers have something in rookie Rashard Robinson. He allowed 11 yards on 1-2 targets to bring his season total to a stingy 31 total yards. Linebacker Nick Bellore also stood out in NaVorro Bowman’s stead. He played more snaps Thursday (68) than his entire five-year career prior to this season, but at times looked like the only 49er capable of making plays versus the run. His eight total stops were double that of his nearest teammate.

PFF Game-Ball Winner: Cardinals’ D.J. Humphries

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