49ers film room: Rookie Mykel Williams run defense review

Today we look at Mykel Williams as run defender.

When John Lynch and Kyle Shanahan talked pre-draft about their team building philosophy heading into the the 2025 season, they spoke about the need to find the “bookend” edge player for Nick Bosa, similar to what they had with Dee Ford. But that doesn’t mean they were looking for a Dee Ford-type of pass rusher.

What it meant was that the team was looking for an every down edge player that had the ability to play the run and set an edge and force opposing offenses into third and long passing situations. The 49ers recent Super Bowl defenses were elite, not because of the pass rush, but because they were exceptional at making teams 1-dimensional by not giving ground in the running game, setting everything up they wanted to do on third downs.

Enter Mykel Williams, who might have been drafted 11th overall based on his run defense tape alone. The defensive lineman from the University of Georgia is known for his strong run-defending abilities and good speed-to-power conversion. His foundational strength and consistency as a run defender provide a reliable baseline, allowing the 49ers to trust his contributions even if his role is specialized initially.

To read more about his physical attributes, which I recommend doing before reading this, see this article below from earlier in the week.

While his pass-rush moves will need further development, the biggest area of impact right away will be felt defending the run and making opposing teams 1-dimensional. The 49ers might have found their bookend to compliment Nick Bosa.

What does the film show about how he’ll be their best asset against the run?

What sets him apart is his combination of raw power and football IQ, enabling him to diagnose plays quickly and react decisively. These qualities ensure he maximizes his impact on the field, proving that a focused skill set can thrive when paired with exceptional physical and mental attributes.

Two plays here against Clemson and Florida State illustrate his adaptability. In the first, Clemson attempts a misdirection power play with an end-around fake, but Williams remains unphased.

He ignores the deceptive motion, shifts his weight inside to mirror the right tackle’s lateral movement, and maintains visual contact with the ball. By attacking the blocker’s outside shoulder, he surges into the backfield to disrupt the quarterback, turning what could have been a touchdown into a stopped play. This sequence highlights his discipline and instinct, qualities that transform sound positioning into game-changing results.

The second play here against FSU features a similar concept but different offensive spacing, with three tight ends aligned near Williams.

Recognizing the altered formation, he immediately bursts past the tight ends at the snap, positioning himself deeper behind the line to contain the edge. Rather than engaging the right tackle, he occupies the running lane and demolishes two pulling linemen, collapsing the play’s structure.

Though he doesn’t reach the ball carrier, his recognition and physicality should have allowed teammates to clean up the play sooner. Instead, the quarterback improvises to salvage yards, a testament to Williams’ ability to dismantle schemes before they fully develop.

Both examples reveal Williams’ nuanced understanding of blocking schemes and his capacity to adjust his approach based on pre-snap cues. Whether shutting down misdirection or overwhelming gaps with calculated aggression, he blends intelligence with brute force to control his area of the field.

Williams play recognition is top level as well. Even when his individual efforts don’t show up on the stat sheet, his presence warps the offense’s plans, creating opportunities for teammates. His ability to read and disrupt the play allows his teammates to make positive plays when he can’t.

Here versus Clemson, the offense is running a toss play to their right. Williams is the defensive end on the left side of the screen. He’s aligned a bit wider to make the crack block harder for the offense to execute.

As Clemson snaps the ball, Williams’s eyes shoot inside the block where he sees the toss play. Recognizing the toss, he gets outside the blocker using his length to ward off the block.

When he gets outside, the next inside receiver must now assist, preventing him from getting to the secondary defender behind Williams. That player makes the tackle as Williams tied up the two edge blockers.

As an edge setter, he’s also been very effective at bottling up opposing team’s running games without making a tackle. The ability to set the edge, identify the run, and being there to stop it are among the most important things to look for when scouting defensive ends.

This is a play that highlights this. Ole Miss is running a wide zone concept against a light box defensive front, making Williams the primary edge setter. On an outside run his way, he needs to be able to spill the runner back inside, shed the tackle, and possibly make the play.

He gets his hands into the chest of the blocker, gets eyes inside to the backfield, reads the running back/quarterback mesh to see where the ball is going and uses his leverage to change direction.

The mesh is designed to slow down the defensive line’s reads identifying where the run is going while the offensive line gets in space. The running back tried to get outside but Williams flashed on the edge and redirected him inside.

Here on this outside zone run in another game against Ole Miss, Williams shows his ability to get low, change his body angle at the point of engagement and dip under the blocker.

Same thing here versus Massachusetts, Williams shoots inside the B-gap by getting lower than the blocker, shifting his weight and dipping his outside shoulder around contact, all while maintaining balance and power into the gap to chase down the running back.

This play below from the Florida game is particularly impressive as well.

Williams is aligned over the tight end to the defense’s left in a 4-down front. His assignment is the C-gap inside the tight end with the offense’s motion to the right. Before the snap, the tight from the back side motions over, creating a favorable blocking surface for the Gators.

On contact, Williams reads the run action and engages inside the blocker’s chest. When the running back takes the toss to the edge, Williams fllips his feet and hips to get back square to the line of scrimmage, limiting the blocking surface the tackle has, and disengages quickly to get upfield penetration and make the stop.

Another play that stands out as highlighting a lot of his traits in one clip is this play against Auburn.

The Tigers are running a quarterback counter run up the middle with three lead blockers. Williams is the wide edge player on the defense’s right and must take on the puller on the edge.

He avoids head-on contact with the blocker by shuffling low and parallel to the line of scrimmage, reading the run action. As the blocker approaches, he dips under and throws his shoulder into the chest of the blocker and disrupts the play with a “box” run fit technique from the outside in.

Final thoughts

Williams demonstrates remarkable discipline and awareness in every clip, yet he consistently delivers explosive plays, bursting into the backfield to disrupt offenses. His aggression is never reckless—instead, it reflects calculated decisions based on alignment and opponent tendencies. This highlights his football IQ and dedication to studying film, showcasing him as both a smart and prepared player.

His ability to balance consistency with game-changing impact sets him apart. By adapting to situations while maintaining a high level of play, he proves his value extends beyond traditional stats. This adaptability makes him a defensive cornerstone, capable of reshaping games with his instincts and execution.

Williams embodies the ideal blend of elite traits and sharp football intelligence. His playstyle redefines defensive value, showing how a player can dominate through both preparation and explosive ability. This rare combination ensures he remains a vital piece of any defensive strategy.