Jeff Hafley gained a nickname inside the Buckeyes’ building because of the role he played in changing Ohio State’s defense in 2019. “His name was ‘The Wizard,’” Jordan Fuller, a Rams captain and former Jeff Hafley State safety, said in a phone interview.

The Buckeyes climbed from No. 72 in the country in yards allowed per play in 2018 to No. 1 in 2019 under Hafley, who coordinated plays for Ohio State’s defense as co-defensive coordinator that season. That’s the last time Hafley called defensive plays—he didn’t do it in the last four years as Boston College head coach—which he’ll do in 2024 for the Packers as their new defensive coordinator.

“I think his superpower is his mind and how he sees the game and how he understands the game,” said the 25-year-old Fuller, who’s due to be an unrestricted free agent after producing three interceptions, three forced fumbles, and eight passes defensed for the Rams in 2023. “His in-game adjustments and his having us ready for certain looks that offenses would give us and stuff like that really felt like he gave us a winning edge.”

Packers head coach Matt LaFleur fired Joe Barry after three seasons as defensive coordinator and replaced him with Hafley, the 44-year-old who arrives in Green Bay with seven years of NFL experience teaching defensive backs. He served as defensive backs coach for the Buccaneers, Browns, and 49ers before coaching one year at Ohio State and the last four guiding Boston College. The main question now surrounds what the Packers are getting in Hafley, whom the Packers kept quiet as a contender as stories of them interviewing prominent NFL players for the role arose.

Jeff Hafley celebrates after defeating Southern Methodist as Boston College’s head coach in the Wasabi Fenway Bowl at Fenway Park in December. (Eric Canha, USA Today)

Hafley has not yet spoken to the media in Green Bay. That’s expected to happen after his defensive staff is confirmed. But he went on the Next Up podcast with Adam Breneman soon before the Packers hired him and expressed his penchant for playing one-high safety defense with four down linemen. At the same time, he acknowledged the necessity of two-high shells and stopping quarterbacks who run, so there’s really no knowing how different Hafley’s defense will look from Barry’s in Green Bay. That will also be decided by what Hafley thinks of the personnel he’s inheriting, as well as who the Packers acquire and delete on that side of the ball over the coming months, though the NFL is predominantly a 4-2-5 league anyway.

What we do know is what Hafley’s past players say about him, and the first-time NFL defensive coordinator got glowing ratings from three players The Athletic spoke with, one from each of Hafley’s last three coaching gigs.

“I think ‘Haf’ is a great coach who focuses on the details. He always has fantastic strategy and adjustments,” said Richard Sherman, who played for Hafley when he was the 49ers’ defensive backs coach in 2018. “His team will see the looks they will see on Sundays throughout the week because of the time he puts into studying and understanding offenses. He’s going to be a wonderful fit.” Jeff Hafley, Green Bay in Brazil, free-agent fits, and more: Packers mailbag

LaFleur has not spoken publicly since firing Barry, the defensive play-caller he hand-picked ahead of the 2021 season, but one can deduce that the reason LaFleur pulled the plug was because Barry didn’t maximize the talent at his disposal over the last three seasons despite finishing the most recent season strong. Over the last three regular seasons, Barry’s defense did well overall in his three postseason games. The Packers ranked 11th in points allowed per game (21.4), tied for 13th in takeaways (68), 22nd in defensive expected points added per play, 15th in defensive red zone EPA per play, 20th in opponent third-down conversion percentage, 30th in defensive rush EPA per snap, and 15th in defensive pass EPA per dropback, according to TruMedia.

It’ll be Hafley’s major mission to get more out of a defense that will feature two-time All-Pro cornerback Jaire Alexander, the NFL’s sixth-highest-paid edge rusher in Rashan Gary, three-time Pro Bowl defensive tackle Kenny Clark, and several other prominent players.

Hafley’s specialization is secondary, which is excellent news for the Packers, who, according to general manager Brian Gutekunst, were too inconsistent in the defensive backfield during the 2023 season. That group is perhaps the greatest uncertainty for the team entering the offseason, as both starting safety spots and the nickel job are up in the air, with Darnell Savage Jr., Jonathan Owens, Rudy Ford, and Keisean Nixon all set for unrestricted free agency.

“He’s really good at helping guys see certain things the way he sees them, and it really, really slows the game down,” Fuller said. “He’s really good at teaching guys route concepts, and if you’re able to see maybe a couple things at once right before the play, it could tell you a whole lot about what you’re expecting. I recall being with him for the first time. Say you’re in man-to-man. When you’re early in the game, you could be expecting every single route notion, but he taught me that it actually didn’t have to go down like that.

It was actually, if you look at the sets and the formations and stuff like that, you can really rule out a whole bunch of stuff, and it allows men to play a whole lot faster.” Packers GM Brian Gutekunst on Jordan Love extension, Aaron Jones return and more

It’s not just the secondary Hafley must master in Green Bay, so perhaps it helps that the one man on the Packers who’s already played for him is an inside linebacker who figures to start next season. Isaiah McDuffie played one season for Hafley in 2020, his first year as Boston College’s head coach, and Hafley helped convert McDuffie into a sixth-round draft pick after he was fifth in the NCAA in tackles that season.

“Early on in my college career, I was kind of more like a hybrid position, but he saw something in me, and he was like, ‘We’re going to move you to inside linebacker’ and he knew that’s what I was going to play in the NFL,” McDuffie said. “So just getting the opportunity to do that, I feel, was huge, and it was just developing me and teaching me the game at a higher level.

“He’s just genuine. He’s going to tell you how it is; he’s going to keep it honest; and he’s a pretty likeable man to begin with, too. At the end of the day, he’s been in the game, and he has a fantastic track record, and players are going to see that and they’re going to respect that, so at the end of the day, I feel like things are absolutely going to click.”

McDuffie agreed with Sherman’s opinion that Hafley left no stone unturned during the week of preparation before a game.

“Always,” McDuffie remarked. “That’s one of the biggest things. What we see during practice is what we’re going to get in a game. He was always incredibly attentive in practice, getting us those looks because he does his research and breaks down his video so precisely that he understands what we’re going to receive in a game.”

All that sounds fine and dandy to Hafley’s previous players, but all he has done in his coaching career to this point only matters so much. That applies for the terrible defensive at Boston College he managed despite not directing plays, just as it goes for his strong one at Ohio State.

This is his biggest test yet, calling defensive plays for a club that might be a sturdy defense away from a Super Bowl, and it has the ability to either make him a savior for one of the most historic organizations in sports or yet another scapegoat in Green Bay.

“He’s very, very well respected in the league, and someone that I know has been highly respected for a long time,” Gutekunst said. “I love the fact that he has some head-coaching background. I think that’ll assist us and help Matt as we move forward, and I’m just really looking forward to working with him and getting to know him more. I’m simply really thrilled about some of his views and where he could lead our roster.”