5 Biggest 49ers Lineup Revelations From Week 1

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The first week of the season is always a good time to see a reveal of what teams plan to do. While we guessed what the San Francisco 49ers would do all season, we were finally able to see what they thought about their roster.
What were the most notable starting decisions?
5 notable starting decisions by San Francisco 49ers
Connor Colby at left guard
The biggest question all offseason was who would start at left guard. Connor Colby was the first person to get a chance, but the team moved him to right guard later in the preseason. However, that appeared to have just been a chance to give rookie Carver Willis a look with the starters. Willis did not win the job, and the team ended up going back to the second-year guard.
Jaden Dugger as the third linebacker
We knew that Dre Greenlaw would start next to Fred Warner. However, when a third linebacker came on the field, it was not clear what the 49ers would do. Luke Gifford had the job, but he has been injured all offseason. Rookie fifth-round pick Jaden Dugger stepped up and took the job. He saw a significant role in his rookie debut, playing the SAM.

Marques Sigle over Malik Mustapha
Mustapha has 22 starts in his first two NFL seasons, and he missed five games last year due to an ACL injury he suffered the year prior. When Mustapha is healthy, he has been viewed as a starter. He has not been fully healthy in training camp, but was active in Week 1. Still, he played special teams and came in for garbage-time work. Besides that, he was the backup to second-year safety Marques Sigle.
Whether Mustapha continues to back up Sigle will be worth watching.
Kaelon Black as RB2
The 49ers were supposed to have a running back competition between Black and second-year Jordan James in training camp. Both were hurt in training camp, so the battle felt unresolved. However, the team made James inactive, and Black had four more rushes than Christian McCaffrey. It is clear who the backup is.
Keion White and CJ West started
Mykel Williams is on the PUP, and Alfred Collins is on the IR. To replace the first two picks in the 2025 NFL Draft, the 49ers called on White and West. West struggled, and rookies James Thompson and Gracen Halton flashed more. Will he continue to start?
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Parker Hurley is a Pittsburgh native and IUP alumni with a deep-rooted passion for football and a decade of experience analyzing the game. Since 2016, he had extensively covered the Chicago Bears, serving as the site manager for Bear Goggles On from 2017 to 2023. During that time, Parker published hundreds of articles per month and led content strategy across written, audio, and video formats. Parker has also produced podcasts, blogs, and YouTube content focused on the Pittsburgh Steelers, NFL betting trends, and league-wide analysis. His work blends film breakdowns, statistical insight, and timely news reaction to deliver clear, actionable content for fans and bettors alike. Now, Parker contributes NFL coverage across multiple platforms, expanding his scope to include teams like the San Francisco 49ers and broader NFL narratives. Whether he’s analyzing rookie development or evaluating playoff contenders, Parker’s top priority is helping readers understand the game on a deeper level. He brings passion, clarity, and consistency to everything he writes, always aiming to educate, engage, and elevate the football conversation.
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