San Francisco 49ers 28, Los Angeles Rams 0

Here are the biggest takeaways and highest-graded players from the San Francisco 49ers' 28-0 victory over the Los Angeles Rams on Monday night.

Quarterback grade: Blaine Gabbert, 48.1

Blaine Gabbert leaves too much on the field

Gabbert struggled with his accuracy at times, as he was off target on more than one easy short throw. He did pick up some yards with his legs (84.2 run grade), which will make the 49ers’ run game more effective going forward.

Top offensive grades:

LT Joe Staley, 83.7

TE Garrett Celek, 74.6

WR Jeremy Kerley, 74.5

TE Vance McDonald, 70.3

RB Shaun Draughn, 65.1

Joe Staley earns third-highest grade among NFL OTs in Week 1

The 49ers’ offense wasn’t highly effective Monday night, even though they managed to score 28 points against the Rams. The big plays and consistent execution were missing, and they will need to generate more plays to beat teams better than Los Angeles. The play of Joe Staley and recent addition Jeremy Kerley were the biggest bright spots for the 49ers' offense. Staley didn’t allow a single pressure on 44 pass-block snaps, and Kerley caught 7 of 11 targets.

Top defensive grades:

CB Tramaine Brock, 91.7

CB Jimmie Ward, 87.1

S Eric Reid, 86.6

LB NaVorro Bowman, 85.9

DI Quinton Dial, 82.6

49ers' cornerbacks lead the way in shutout

This was a poor display of offensive football from both teams, but the 49ers never really allowed the Rams’ offense to do anything. San Francisco's defenders on all three levels graded very well against L.A., but expectations of similar performances will have to be tempered, as the Rams have one of the league’s worst offenses. Tramaine Brock was the 49ers’ highest-graded defensive player; he was targeted eight times in coverage and yielded three catches for only 16 yards, and Case Keenum’s QB rating when throwing into Brock’s coverage was just 45.8.

Quarterback grade: Case Keenum, 43.4

Case Keenum underwhelms in season debut

Case Keenum spent most of the game Monday night staring at a tablet screen, wondering what went wrong. He only completed 3 of 10 passes that were targeted 10 yards or more downfield. Keenum’s QB rating when blitzed by the 49ers was 4.9.

Top offensive grades:

RB Todd Gurley, 74.4

WR Kenny Britt, 73.7

LG Rodger Saffold, 71.7

RG Jamon Brown, 49.8

WR Brian Quick, 49.5

Solid debut for Todd Gurley, but no support from Rams around him

The Rams' offensive line failed to generate much push in the run game, and allowed 19 pressures on Keenum. L.A. dropped six passes against the San Francisco. Running Back Todd Gurley forced seven missed tackles on his 17 rushing attempts, but other players are going to need to step up for the Rams’ offense, or this is going to be a long and ugly season for the team.

Top defensive grades:

DT Aaron Donald, 93.3

S T.J. McDonald, 86.8

DT Michael Brockers, 83.1

S Maurice Alexander, 81.9

LB Alec Ogletree, 78.5

DT Aaron Donald continues his disruptive ways

Aaron Donald was our top player in the league last season, and looks to once again be playing at a ridiculously high-level, as he was dominant before his ejection. Donald earned a 94.0 pass-rush grade and a 84.8 run-defense grade against the 49ers as he continued to get into the backfield so quickly that plays were almost instantly doomed.

PFF Game Ball Winner: 49ers CB Tramaine Brock

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