Head Coach Jeff Hafley and the rest of the Miami Dolphins' leadership have been hard at work filling out his first coaching staff, and they just filled their most important remaining spot. Green Bay Packers linebackers coach Sean Duggan has been brought on board to be the new defensive coordinator, replacing Anthony Weaver.
The #Dolphins are set to hire #Packers linebackers coach Sean Duggan as their defensive coordinator, sources tell @CBSSports.
— Matt Zenitz (@mzenitz) February 1, 2026
Worked under Jeff Hafley in Green Bay and at Boston College. Now set to join him in Miami. Coached players like Quay Walker and Edgerrin Cooper in GB. pic.twitter.com/NGz1oXhEii
Duggan coached under Hafley since 2020, first at Boston College from 2020 to 2023 before following him to Green Bay the last two seasons. He was the rumored top candidate for some time, but Miami likely waited to see if Weaver would potentially earn a HC job elsewhere before officially moving on. Had he gotten one of the final job openings, they would have netted two third-round compensatory picks.
Instead, the Cardinals and Seahawks went with Mike LaFleur and Klint Kubiak, respectively, paving the way for Duggan's arrival in South Beach.
Sean Duggan will be tasked with helping Miami Dolphins HC Jeff Hafley implement his defensive vision
With Hafley expected to call the defense himself, at least for now, Duggan's role as DC will be different from what Weaver's was under Mike McDaniel. Instead of focusing on calling plays for the unit, he will be responsible for helping Hafley teach his scheme and get the roster up to speed. There is going to be a lot of roster turnover this offseason, so having another coach who knows the defense on the staff was a smart move.
Could Hafley have chosen to add a more experienced DC to help build upon his existing scheme? Absolutely, and with Bobby Slowik being retained as the offensive coordinator, having a veteran coach in one of the top coordinator spots may have been a smart decision.
It's relatively common to see young HCs try to bring on a coordinator or other high-ranking assistant who has more experience than they do, especially if they have HC experience themselves. Choosing to go with someone like Duggan, whom Hafley clearly trusts to help him sort out the defense, is still a fine direction to go in, however.
That will be especially true if Hafley has plans to eventually settle in as more of a CEO-style coach, potentially handing over the defense to Duggan once they feel the time is right. Many defensive-minded coaches eventually go in that direction, as it gives them more time to focus on the team as a whole instead of needing to spend the bulk of their energy coaching the defense.