2 Defensive Changes 49ers Must Make After Beating Rams

These changes will improve their defense.

Sep 11, 2026; Melbourne, Victoria, Australia; Los Angeles Rams quarterback Matthew Stafford (9) throws the ball under pressure from San Francisco 49ers defensive end Nick Bosa (97), defensive tackle C.J. West (99) and defensive end Keion White (56) in the first quarter during the 2026 NFL Melbourne Game at Melbourne Cricket Ground. Mandatory Credit: Kirby Lee-Imagn Images | IMAGN IMAGES via Reuters Connect

It's difficult to nitpick much about the San Francisco 49ers after their dominant Week 1 win in Australia against the Los Angeles Rams.

Both sides of the ball executed at a high level. However, two defensive changes stand out as improvements for the 49ers to make immediately after beating the Rams.

Malik Mustapha in, Ji'Ayir Brown out

It's time to end Ji'Ayir Brown's tenure as the starter and let Malik Mustapha take over. Brown was responsible for a couple of backbreaking mistakes in the first half for the 49ers' defense.

One of them happened with less than two minutes left in the first quarter. Brown was in position to tackle Puka Nacua and limit the damage, but he oddly decided to play the ball.

That allowed Nacua to break free and reel off a 41-yard play. The Rams ended up on the 49ers' eight-yard line. Shortly after, he had a chance to stop Kyren Williams from scoring.

Yet again, Brown made a boneheaded decision by lowering his shoulder on Williams. He doesn't connect cleanly, allowing Williams to get in for the score.

Brown is the president of bad decisions. Maybe if he cleaned it up, he could be decent, but this is what he does. Put Mustapha in over him immediately, and watch the mistakes decline.

More Gracen Halton, less C.J. West

Another player who was baffling was C.J. West. Unlike Brown, the 49ers can't bench West. They need to use him because their defensive tackle depth is lacking.

However, they can remove him as a starter and keep him in a rotational role. There's no hope with West at this point. He was playing late in preseason games for a reason.

Early on, when the Rams were having massive success running the ball, it was West who was getting blocked into the parking lot of the stadium. He's just a sled out there.

Meanwhile, the defensive front settled when the 49ers started playing rookie Gracen Halton more. That is their answer to shoring up the position.

Halton is better than West, and he provides hope as a rookie. The arrow is pointing up with him, which isn't with West. He hasn't shown any signs of improving.

Anytime he is in, offenses will know they can run the ball successfully. Halton will probably struggle as well, but his floor is already higher than West's. The 49ers can live with that.

Less West and more Halton, and bench Brown for Mustapha to improve the defense.