The San Francisco 49ers enter Thursday night’s divisional matchup against the Los Angeles Rams with a defense that looks different from the one fans expected coming into the season. Injuries have reshaped the depth chart across the front seven, forcing younger players and rotational pieces into starting roles. With that in mind, here are three defenders who will be critical if the 49ers want to slow down the Rams’ offense.

Yetur Gross-Matos – Defensive End

With Nick Bosa sidelined, Yetur Gross-Matos finds himself in the unenviable position of filling the shoes of the league’s best pass rusher. Acquired to bring depth to the defensive line, Gross-Matos now needs to deliver consistent pressure off the edge against Matthew Stafford. The Rams’ offensive line has been vulnerable at times, and San Francisco’s best chance at disrupting their rhythm will come from Gross-Matos generating heat. He doesn’t need to replicate Bosa’s production, but he does need to win one on one matchups and collapse the pocket enough to make Stafford uncomfortable.

Kalia Davis – Defensive Tackle

The interior of the defensive line also took a hit with Kevin Givens landing on the injured reserve. That opens the door for Kalia Davis to take on the role. Davis’ job will be to clog rushing lanes against Kyren Williams and provide push up the middle to help collapse the pocket. With so many injuries, San Francisco will lean heavily on Davis’ ability to anchor the middle and prevent the Rams from establishing a run game. If he holds his ground, it will free up linebackers and edge rushers to make plays around him.

Fred Warner – Linebacker

At the heart of it all is Fred Warner, who may be more important this week than ever. As the vocal leader and centerpiece of the 49ers’ defense, Warner will be tasked with keeping this patchwork unit organized and confident. Beyond the intangibles, Warner’s sideline-to-sideline range will be critical in limiting chunk plays to fellow BYU grad, Puka Nacua. With so many regular starters missing, Warner has to play like the All-Pro he is and set the tone for everyone else around him.

Final Word

The 49ers’ defense has been battered by injuries, but the next-man-up mentality will be on full display Thursday night. Gross-Matos’ ability to pressure the edge, Davis’ strength in the middle, and Warner’s leadership and playmaking will determine whether San Francisco can hold its own against a dangerous Rams attack. If those three rise to the occasion, the 49ers have a chance to impose their will in Los Angeles.