Position-by-position grades from the 49ers embarrassing 31-17 loss to Cardinals

Everything seemed to be breaking the 49ers' way this week. After a disappointing start to the season, the Niners defeated the Chicago Bears last week and seemed ready to get on a roll. They welcomed several key players back from injury this week while their opponent, the Arizona Cardinals, lost their star quarterback (Kyler Murray) and wide receiver (DeAndre Hopkins). Yet, San Francisco laid an egg in an embarrassing 31-17 defeat with all that in their favor.

The 49ers disappointing performance falls on more than just the players, but several position groups failed to live up to the team’s expectations.

Quarterbacks: B

For the second straight game, Jimmy Garoppolo played well enough to win. He completed 28 of his 40 pass attempts for 326 passing yards, two touchdowns, and an interception, but his numbers were held down by some struggles on the last few drives after the game was decided.

While head coach Kyle Shanahan has insisted that the 49ers have not lost because of Garoppolo all season, Sunday’s loss to the Cardinals was the first time that was true. When it mattered, Jimmy G did not commit any turnovers and was leading the offense on two promising drives early that were torpedoed by fumbles by his receivers.

Running backs: B

The 49ers continued leaning heavily on rookie Elijah Mitchell, who was once again impressive. While the Cardinals' defensive scheme and early lead forced San Francisco away from the run game, Mitchell still accrued 36 rushing yards on eight carries and caught all five of his targets for 43 receiving yards. Kyle Juzczyk and JaMycal Hasty were also targetted six times and recorded five receptions for 25 yards. Niners’ runners were not asked to do a lot on Sunday, but they did what they were asked.

Tight ends: C+

In George Kittle’s first game back from injury, Shanahan immediately took advantage of having another dynamic weapon. Kittle was Garoppolo’s top target from the jump, but after their first drive stalled, the veteran tight end hauled in a pass over the middle that could have sparked a big drive. Instead, Cardinals cornerback Byron Murphy punched the ball loose from behind and lost the first fumble of his career. Still, despite the turnover, Kittle caught six of his eight targets for 101 receiving yards and a touchdown.

Wide receivers: C

If there’s one positive takeaway from an otherwise uninspired performance, Brandon Aiyuk put together his best performance of the season. He racked up six receptions (eight targets) for 89 receiving yards and a touchdown. Unfortunately, his otherwise great day was overshadowed by a costly fumble inside the red zone.

Deebo Samuel was solid once again as well, racking up 63 receiving yards on five catches. While everything else went wrong, the 49ers receiving corp looked as close to what fans envisioned this offseason as it has this season. It might not mean that much if the 49ers cannot put together a winning streak soon, but it seems like they finally have the dynamic Aiyuk/Samuel/Kittle trio many envisioned.

Outside of Samuel and Aiyuk, though, the 49ers once again failed to get anything from a third receiver. Mohammed Sanu made just one catch for five yards on the day while committing a costly offensive pass interference penalty in the red zone.

Offensive line: D

Once Mike McGlinchey left the game with a knee injury in the first half, the 49ers confusingly deployed Tom Compton at right tackle instead of swing tackle Jaylon Moore. Compton had one of the worst performances by a Niners’ lineman this season. Despite playing less than three quarters, he allowed multiple sacks and consistent pressure. The rest of the o-line seemed to fall apart as soon as McGlinchey left, with right guard Dan Brunskill particularly struggling to contain Arizona’s pass rush as well. It’s hard to delineate who is responsible, but it seemed like Compton just lacked any rapport with his fellow blockers.

Defensive line: C+

The 49ers run defense has yet to recover from Javon Kinlaw’s season-ending injury. Kinlaw has been very effective when healthy, clogging up the run despite his struggles as a pass rusher. Unfortunately, the 49ers have allowed more than 100 yards rushing in each of the last four games without him on the field, with the Bears and Cardinals eclipsing 165 yards on the ground.

Cardinals head coach Kliff Kingsbury relied on misdirection, screens, and short passes to dink-and-dunk the 49ers' defense all night. Arik Armstead and Nick Bosa had some impressive plays overpowering the Cardinals line, but the Niners front, particularly Bosa, have been weak against those attacks all season.

Linebackers: D

Azeez Al-Shaair looked like he had put his tackling issues behind him this season. Still, those struggles returned with a vengeance on Sunday, including on a third-and-18 pass to James Conner that could have forced Arizona to punt from deep in their own territory. Instead, the Cardinals scored a touchdown on the drive and took a 14-0 lead.

Fred Warner was better than Al-Shaair, but even he was less impactful than the 49ers faithful have come to expect from the defensive captain. Without a dominant performance from the defensive line and an even further depleted secondary, Warner needed to come up with a big play. Bosa gave him a shot when he forced a fumble that fell right at his feet, but the BYU alum could not recover the ball.

Cornerbacks: D

It’s the same story every week in different words with the 49ers cornerbacks. Some combination of missed tackles and penalties has tanked the defense on multiple occasions. This time, Josh Norman was hit with an inexcusable taunting penalty while Emmanuel Moseley and Dre Kirkpatrick struggled with tackling all day.

Safeties: F

The 49ers dearly missed Jimmie Ward and Jaquiski Tartt on Sunday. Rookie Talanoa Hufanga has had his moments this season but consistently fell victim to Arizona’s misdirection. For all the complaints levied at Ward and Tartt, their absence this week showed how much defensive coordinator DeMeco Ryans has been relying on his veteran safeties to clean up messes created by the unit’s weaknesses at the first and second levels. Hufanga and veteran journeyman Tavon Wilson was simply not up to the task.

Special teams: B

No one missed a field goal, Aiyuk had an impressive punt return, Robbie Gould made all of his attempts.