In a stunning turn of events, the San Francisco 49ers have unearthed a gem in their rookie linebacker, Mykel Williams. Selected in the first round of the 2025 NFL Draft, Williams has quickly become the linchpin of the 49ers’ revamped run defense, addressing a critical weakness that plagued the team in the previous season. Despite modest traditional statistics, Williams’ impact on the field is undeniable, earning him praise as head coach Kyle Shanahan’s secret weapon.
A Quiet Stat Sheet, A Loud Impact
Through the first two games of the 2025 season, Mykel Williams has recorded just six tackles and zero sacks. On paper, these numbers might suggest a muted start for the rookie. However, advanced metrics paint a far different picture, revealing Williams as one of the most influential defensive players on the 49ers’ roster.
When Williams is on the field, opposing offenses have managed a paltry 25.8% success rate on rushing plays. In stark contrast, that number balloons to 66.7% when he’s off the field. This dramatic discrepancy underscores Williams’ ability to disrupt running plays and set the tone for San Francisco’s defensive front. His presence alone forces offenses to adjust their strategies, often double-teaming him to neutralize his dominance at the line of scrimmage.
Why Williams Excels Against the Run
What makes Mykel Williams so effective? It starts with his immovable presence. Standing tall and powerful, Williams is a brick wall that offensive linemen struggle to displace. His ability to hold his ground in run defense allows the 49ers’ linebackers, like Dee Winters, to roam freely and make plays. Winters, who has drawn comparisons to a prime Dre Greenlaw, owes much of his early-season success to Williams’ ability to occupy blockers and create clean opportunities for tackles.
Williams’ versatility further amplifies his value. Capable of lining up as a defensive tackle or defensive end, he brings a dynamic skill set that the 49ers have lacked since the departure of Arik Armstead. Last season, the 49ers’ run defense faltered after releasing Armstead, their former standout run-stopper. While the decision to move on from the aging veteran was justified, the team struggled to fill the void—until Williams arrived.
Filling Arik Armstead’s Shoes—and Then Some
Arik Armstead, now with the Jacksonville Jaguars, was a cornerstone of San Francisco’s run defense for years. However, his limitations became apparent against mobile quarterbacks, who frequently exploited his lack of agility. Williams, on the other hand, offers a significant upgrade. Not only can he stonewall running backs, but he also has the athleticism to contain elusive quarterbacks, making him a more versatile asset than Armstead ever was.
While Armstead took five years to develop into a Pro Bowl-caliber player (though never earning the honor), Williams appears to be on a faster trajectory. His potential to become both an elite edge rusher and a dominant interior defender sets him apart. Unlike Armstead, who transitioned to a full-time interior role later in his career, Williams’ ability to excel in multiple positions gives the 49ers’ defensive coordinator unparalleled flexibility.
A Foundation for Success
Even if Williams never develops into a prolific pass-rusher, his prowess in run defense ensures a long and successful NFL career. Every team craves a player who can anchor the defensive line and shut down the opponent’s ground game. However, playing alongside stars like Nick Bosa and Bryce Huff, Williams is likely to see plenty of pass-rushing opportunities. In situations like third-and-long, where offenses focus on Bosa and Huff, Williams could rack up sacks by capitalizing on one-on-one matchups—much like Armstead did during his standout 2019 season.
At just the start of his rookie campaign, Mykel Williams is already transforming the 49ers’ defense. His ability to fix the team’s biggest flaw—a porous run defense—has been nothing short of astonishing. With his blend of size, strength, and versatility, Williams is poised to become a cornerstone of San Francisco’s defense for years to come. As he continues to develop, the NFL will soon learn what 49ers fans are already discovering: Mykel Williams is no ordinary rookie, but a game-changer who could redefine the team’s defensive identity.