49ers vs. Cardinals: Position grades and analysis for San Francisco

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San Francisco 49ers vs. Arizona Cardinals Week 5 position grades and analysis

San Francisco 49ers FS Adrian Colbert (Photo by Thearon W. Henderson/Getty Images) /

Defensive Grades

Defensive Line

The interior of the 49ers’ defensive line excelled, as tackles Sheldon Day and Earl Mitchell both played their best games of the season, and fellow tackle DeForest Buckner was his normal disruptive self. Defensive ends Arik Armstead and Cassius Marsh also had good games, but DE Solomon Thomas was virtually nonexistent. Although it likely sounds like a broken record, the 49ers need to improve their edge pass rush, as the team logged just a single sack. Expect this problem to continue throughout the season.

Grade: B+

Linebacker

The 49ers’ linebackers were a mixed bag on Sunday. Rookie MIKE linebacker Fred Warner was improved from recent weeks, and WILL linebacker Reuben Foster was serviceable but has yet to return to his dominant 2017 form. SAM linebacker Malcolm Smith continues to miss tackles, but at least this week, his errors were simply physical and not mental as well. So far this season, the expensive Smith hasn’t been an improvement over last year’s disappointing SAM linebacker Eli Harold.

Grade: B

Secondary

On Arizona’s first offensive play from scrimmage, free safety Adrian Colbert ran right by streaking wide receiver Christian Kirk, who caught a deep pass attempt by Rosen for a 75-yard touchdown score. Given Colbert’s play this season, San Francisco’s coaching staff may have overestimated the second-year player’s ability to be the team’s long-term starter at free safety. Cornerback Ahkello Witherspoon, who was chasing Kirk from behind on the play, allowed a number of catches throughout the day, as did nickel corner K’Waun Williams. Cornerback Greg Mabin played well for a second consecutive week, and should find more playing time moving forward. CB Richard Sherman didn’t allow a reception despite his early return from injury, and strong safety Jaquiski Tartt played well — particularly against the run — in his first game back since his Week 2 injury. Overall, the 49ers’ secondary came away with a good statistical day that was mostly a product of poor quarterback play.

Grade: C+