Still, Brown believes that the early returns have been promising.
"We don't have a split of old and young, we don't have guys that hate their coach, so I think for the first four months it's been about as good as it can be," he said.
One of the biggest questions for the Tar Heels will be the status of their defensive front seven, a group that allowed 34.6 points per game last season and lost their best pass rusher Malik Carney.
"We are really, really thin in the defensive line, and we're thin at linebacker," Brown said. "I told the coaches, we've got to coach them up. It doesn't matter whether they think they're experienced or even talented. Get the guys playing hard, get them in the right place, and they'll play better than they have in their past."
Regarding injury concerns, Brown also said that many Tar Heels will sit out the Spring Game, and "We'll be a lot deeper in the fall than we are today."
"Guys have to get healthy," he said. "We're really studying why they've had so many injuries here the last two years."
Among the healthy Tar Heels, spring standouts include rising sophomore Trey Morrison, who started 10 of 11 games last season at nickelback.
"He's very smart, he has excellent instincts and he's tough," Brown said. "He's passionate, he loves the game. He plays like an older guy. In fact, we have to hold him out of some things ... we have to make sure to keep him fresh."
Another is linebacker Jeremiah Gemmel, a rising redshirt sophomore who Brown described as "a guy with instincts."
"He's really fast with instincts, loves to play," Brown said. "He will hit you, so he should be a good linebacker in time."
Brown and his staff have emphasized the importance of talking on the field, something Gemmel seems to have taken to heart.
"On defense, I always feel like we always play at our best when we're communicating," Gemmel said. "When we're not communicating we have lapses, miscues. If I can talk to the D-line and get them on the same page, talk to the safeties and corners and get them on the same page, we'll have a way better chance to make plays."
Under Brown, the Tar Heel defense has incorporated many more zone principles, a scheme that rising redshirt junior safety D.J. Ford, another spring standout, described as "controlled chaos."
"It's foreign to someone who doesn't know what they're looking at," Ford said. "It's kinda like trying to read Chinese or something."
Ford is just one Tar Heel who has relished in the head coaching change, a change that seems to have energized and given fresh opportunities to the entire team.
"Nobody was ahead of anyone else," Ford said. "We all just compete, and push each other.
"We're constantly getting better."
Sam Jarden contributed to reporting for this story.
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