MADISON – Not too long ago, D'Cota Dixon was a lost soul in the Wisconsin defense.

He was playing out of position, dealing with an injuries and, save for one game in 2015, was stuck as a role player. Now he’s become one of the Badgers’ hard-hitting players, leveling big hits and making big plays in critical situations.

There’s been a lot of changes in Dixon’s game over the last 10 months, but none bigger that having defensive backs coach Jim Leonhard pushing him every day.

“I take everything he says to the heart,” Dixon said. “I take it serious because he’s real firm in what he talks about. It’s about learning every day, being a sponge and soaking up knowledge.”

Five games into his coaching tenure, there’s no denying the impact the former Wisconsin All-American has had on the Badgers’ secondary. Having to replace three starters entering this season, Wisconsin has seen all four starters make a tangible impact.

Cornerback Derrick Tindal leads the team with three interceptions and is tied with cornerback Sojourn Shelton with five pass breakups. Free safety Leo Musso is fourth on the team with 23 tackles to go along with an interception and a 66-yard touchdown off a fumble recovery against Michigan State. That fumble was caused by Dixon, who has a sack, three quarterback hurries, two pass breakups and the game-clinching interception against LSU.

“It’s been fun for me to see our players work with Jim and what they take away,” head coach Paul Chryst said. “Jim’s got a great ability to make a coaching point, yet it’s simple. It’s not easy, but it’s clear. I’ve always felt this, he’s a unique individual. I was fortunate to be a coach when he was playing. He’s not coaching because he was a great player at Wisconsin or a great player in the N.F.L. He’s a really good coach.”

No.11 Wisconsin (4-1, 1-1 Big Ten) enters the bye week ranked fifth in the nation in scoring defense, giving up 12.2 points per game. Boil the number down further, Wisconsin has given up just five touchdowns (two rushing, three passing) with its defense on the field and only one over 13 yards.

While the Badgers are 34th in the country against the pass (201.0 yards per game), the defense’s seven interceptions (six by the secondary) are tied for 11th in the country.

“I think they’re very gritty,” Leonhard said of the defense. “They don’t necessarily care who gets credit, who makes the play. They’re going to play hard, and they’re going to put it all out there. They’re going to be physical and make you beat them every single snap.”

Leonhard’s statement encapsulates his entire playing career. The Ladysmith, Wis., native walked on to Wisconsin to 2001 having no scholarship offers, likely because his 5-8 frame wasn’t prototypical for the college game. With his speed, athleticism and intelligence, Leonhard was a three-time All-American and finished his college career with 281 tackles, 21 interceptions and 50 pass breakups (25 coming his sophomore year).

Though he went undrafted, Leonhard put together a 10-year N.F.L. career with Buffalo, Baltimore, the New York Jets, Denver, New Orleans and Cleveland. He finished his professional run as a safety and returner with 14 interceptions and 427 total tackles.

It’s not often a head coach can hire an assistant who was a successful college player, N.F.L. player and highly regarded as a “coach” on the field. The added bonus of Leonhard having thrived at Wisconsin made him a home run hire for Chryst to replace Daronte Jones.

“When you talked to people in the N.F.L., the amount of respect they have for him, I was always lucky when I was an assistant here and he’d come back and we’d talk a lot,” Chryst said. “When he was playing, he would come back and he would grab safeties. If guys ever wanted to ask him something, he was so willing to share and talk about it. He gave his time. If a guy wanted to learn, he was going to try and help him.”

One of those players to take advantage of Leonhard’s presence was Dixon.

Recruited as a talented, hard-hitting safety, Wisconsin’s former coaching staff put Dixon at outside linebacker to bring that physical nature closer to the line of scrimmage. The move didn’t pan out. Dixon felt out of place at the position and saw his season end before conference play to fix a labrum injury.

He was moved to safety last season and played sparingly outside of filling in for Michael Caputo in the season opener.

When Caputo graduated, Dixon was given the first opportunity by Leonhard to replace the senior and he hasn’t given the job back.

“Nothing against Coach Jones, but I feel Coach Leonhard simplified things a little bit better for me,” Dixon said. “He helps me understand the defense a little bit more, understand techniques a little bit differently. He comes from a player’s perspective from a college All-American to a 10-year veteran in the N.F.L., (so) anything he says we’re all going to listen. Everybody dreams about going to the N.F.L., so I’m going to listen to what he has to talk about.”

That instant credibility was evident right away in the spring. During one of their first practices as a group, Leonhard was injecting his competitive nature in a simple technique drill as he talked about technique and playing a receiver through different breaks.

Dixon can’t remember the last time the entire group was so locked into a drill, something that has set the tone for Wisconsin’s secondary a little more than a third of the way through the season.

“Having him as our coach really is an honor,” Dixon said. “We really have a lot of faith in him and I know he does in us. A guy like that makes you want to play for him. A coach like that is a dream coach.”