MIAMI GARDENS — New Miami Dolphins coach Jeff Hafley’s background is on the defensive side of the ball, but more specifically in the secondary.

So, as the Dolphins under Hafley and new general manager Jon-Eric Sullivan are expected to build a foundation around physical play in the trenches, they’re also likely to operate with an emphasis on strong defensive backs.

For a regime that will need to construct its roster through the draft to start off, Sullivan could foreseeably invest his first draft pick on one of this year’s best cornerback or safety prospects.

Miami has ample youth on both sides of the ball, as drafted by former GM Chris Grier at the end of his tenure. The team’s first- and second-round picks the past two seasons came in the trenches: defensive tackle Kenneth Grant and left guard Jonah Savaiinaea in 2025 and edge defender Chop Robinson and left tackle Patrick Paul in 2024. Additionally, the Dolphins picked up fellow defensive tackles in Jordan Phillips and Zeek Biggers later in the last year’s draft.

When Miami is first on the clock in late April, with the No. 11 pick, a number of quality defensive back prospects figure to go in that range, namely cornerbacks Mansoor Delane from LSU and Jermod McCoy from Tennessee and safety Caleb Downs of Ohio State.

The Green Bay Packers, while Sullivan was in their front office, drafted a defensive back first in five of eight drafts from 2014 to 2021, twice doubling down on DBs with the first two selections.

But before the Dolphins seek solutions through the draft, they will be figuring out what to do with their own free agents, as well as outside free agents and developing young players already under contract.

The Dolphins’ top internal free agent at cornerback is Rasul Douglas. After signing within two weeks of the open to the 2025 regular season, Douglas allowed a passer rating against of 73.0, a very good number in 15 games and 13 starts, while giving up just 5.6 yards per target, deflecting 13 passes and intercepting two.

Douglas said, at season’s end, he enjoyed the season with the Dolphins, especially with the coaching staff letting him play his game.

Now, last season’s defensive coordinator, Anthony Weaver, and cornerbacks coach Mathieu Araujo are not part of this new staff, but under Hafley, he’s bringing in coaches in the secondary with previous ties to Douglas. New cornerbacks coach Jahmile Addae was with him in 2024 in Buffalo, and defensive backs coach Ryan Downard had him in Green Bay before that.

Douglas also appreciated bonds made in Miami’s locker room.

“I got really close with some of the guys that work hard, guys that are always, just like me, stay in the building, like to work,” he said.

Fellow cornerback Jack Jones and safeties Ifeatu Melifonwu and Ashtyn Davis all told the South Florida Sun Sentinel ahead of the Dolphins’ season finale they would like to return.

“I would love to be here. I’ve really enjoyed my time being down here,” Davis said. “Maybe we can make that happen. I would love to make that happen.”

Said Melifonwu: “Yeah, definitely. I like it here.”

And Jones: “I’d love to play for Miami.”

For Jones, 2025 with the Dolphins marked growth for the player once deemed to have attitude and off-the-field issues.

“This year, it taught me a lot. I learned a lot. I grew a lot. And I don’t take this year for granted,” Jones told the Sun Sentinel before season’s end. “I think this was a stepping-stone year where I’m crossing over into who I want to become and leaving who I was behind, so I appreciate everybody, part of the Miami Dolphins organization that helped me get to this point in my life.”

In what ways has he grown?

“I say off the field and just my attitude, not letting everything get to me. It’s more so personal,” Jones said. “Don’t let things weigh too much on me, control what I can control and never get too high or too low.”

What stood out to Davis in Miami after his first five seasons with the New York Jets?

“Everyone’s bought in. Everyone’s pretty close,” he said. “And when you’re playing for your brother and not just another guy on the field, you’re going to give it everything you have.”

However, it’s unlikely all of them will return.

“I’m going to miss playing with some guys, but that’s just the nature of the NFL,” Melifonwu said.

All the expiring contracts in the secondary, though, also afford Sullivan and Hafley an opportunity to bring in their own players at those positions.

After Grier traded for safety Minkah Fitzpatrick ahead of last season, Sullivan has him under contract and will decide whether to keep him on the roster, find a trade for draft capital and salary cap savings or release him. The Dolphins would save $5.85 million toward the cap if they cut him or $15.6 million if they do so with a post-June 1 designation.

Beyond the veteran free agents, which also includes nickel cornerback Kader Kohou after his preseason ACL tear, the Dolphins return rising second-year cornerback Jason Marshall and safety Dante Trader Jr. Miami also has cornerbacks Storm Duck and JuJu Brents coming off season-ending injuries last season.

Before he was Packers defensive coordinator and Boston College head coach, Hafley doubled as defensive backs coach when he was co-defensive coordinator at Ohio State in 2019. He has coached DBs at the professional level with the San Francisco 49ers, Cleveland Browns and Tampa Bay Buccaneers, as well as with Rutgers, Pittsburgh and Albany in college football.