LOS ANGELES -- The Los Angeles Rams will be without star running back Todd Gurley on Sunday, but nothing changes for the 49ers’ defensive approach.
“Same formula, same mindset,” 49ers linebacker Fred Warner said. “Get to third down, and let the big guys eat.”
The key to the 49ers’ improved pass rush has been the team’s ability to shut down the opposition's running games on first and second downs. Defending third-and-long situations has been advantageous for the 49ers, with Nick Bosa, DeForest Buckner, Dee Ford and Arik Armstead each recording multiple sacks through four games.
“For us, our philosophy has always been that we’re going to be as sound as possible on first and second down,” 49ers defensive coordinator Robert Saleh said. “We eliminate explosives, that’s the No. 1 rule to our defense -- to make sure that we’re going to eliminate explosives at all costs.
“You can’t be sound unless you’re sound in the run game first.”
The Rams (3-2) have run the ball successfully on first downs with Gurley as the main back, averaging 4.6 yards per attempt. But Gurley is out for Sunday’s NFC West matchup due to a quadriceps injury.
Coach Sean McVay will mostly turn to Malcolm Brown and rookie Darrell Henderson Jr. The Rams also promoted running back John Kelly from the practice squad Saturday. Brown, a fourth-year player from Texas, has rushed for 114 yards and two touchdowns on 26 carries as Gurley’s backup this season.
“I feel like they’re still going to run their offense,” Warner said. ‘I know they have great backups behind Todd. We’re still going to execute our game plan and try to get after them.”
The 49ers’ defense has surrendered an average rush of 3.85 yards on first-and-10 situations. They rank fifth in the NFL, allowing just 81.8 yards rushing per game. The 49ers’ ability to keep quarterback Jared Goff in third-and-long situations could be a huge benefit against the Rams’ explosive passing attack.
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San Francisco generally has maintained a four-man pass rush, but Saleh has the opportunity to be more complex with coverages and pressures on third downs when there is no threat of the run in those long-yardage situations.
The 49ers have recorded 13 sacks through four games while holding on, along with the New England Patriots, as one of just two unbeaten teams in the NFL.
“On third down, it gives you the flexibility to get a little bit more exotic because you’re not worried about the run game as much,” Saleh said. “Now you can cheat coverage, you don’t have sell out with an eight-man box, you don’t have to be perfect in the run game. You still want to have an idea of where people fit, but odds are you’re playing for pass.”