The Miami Dolphins have a new defensive coordinator in Sean Duggan; his relationship with Jeff Hafley and his know-how can lead to a big evolution.
With training camp a few days away, the Miami Dolphins will soon take the field at the Baptist Health Training Complex with a new voice leading the defense.
The Dolphins hired Sean Duggan this offseason to replace Anthony Weaver.
Duggan, 33, is taking on his first true career defensive coordinator role after serving as a co-defensive coordinator at Boston College in 2023.
While Weaver helped establish a physical, in-your-face style of play over the past two seasons, the new regime led by general manager Jon-Eric Sullivan and head coach Jeff Hafley decided it was time for a change.
There is some familiarity, as the three worked together in the Green Bay Packers' organization, with Duggan coaching the linebackers in 2025.
Rather than completely changing the foundation, the first-time coordinator will look to add his own ideas while maximizing a roster filled with talented defenders.
The Dolphins did their due diligence this offseason, extending inside linebacker Jordyn Brooks to a three-year contract. Brooks is a leader on the defense who can continue to impart his work ethic to the unit.
Hafley indicated he is excited to work with Chop Robinson, who could take a big step under Duggan and the Dolphins head coach.
Tyrel Dodson, who was acquired off waivers from the Seattle Seahawks in 2024, also had a solid year. And second-round pick Jacob Rodriguez continues to garner praise and could work himself into a strong rotational position behind Brooks and Dodson.
Longtime veteran Zach Sieler also remains a cornerstone on the defensive line. He has made a name for himself after joining the Dolphins in 2019.
Sieler started all 17 games last season and served as one of Miami's team captains.
The defensive front will likely be a major part of Duggan's plans.
Miami has invested heavily in its pass rush, minus Bradley Chubb and Jaelan Phillips, and Duggan is expected to find creative ways to move defenders around the formation.
By creating different matchups and pressure looks, the Dolphins hope to make opposing offensive lines uncomfortable throughout the season.
The linebacker position could also take on aan even bigger role in Duggan's plans.
Duggan is expected to value players like Brooks and Rodriguez who can handle multiple responsibilities, whether that means stopping the run, dropping into coverage, attacking the quarterback on blitzes, or handling green-dot duties, which involve receiving the defensive play call from the sideline and relaying it to teammates before the snap.
There will naturally be some hiccups as Duggan steps into his first coordinator role.
Training camp will provide the first opportunity to see how players respond to his system and how quickly the defense develops an identity.
If Duggan's vision matches Miami's expectations, the 2026 season could mark the beginning of a new chapter for the Dolphins defense.
For Dolphins news, analysis, and more, join the community HERE. Creating an account is completely free.
