A ruckus inside the Gophers locker room could be heard by reporters sitting in an adjacent room at Wisconsin's Camp Randall Stadium in late November 2018.

P.J. Fleck's team had just defeated its border rival for the first time in 14 years, and his players were euphoric. A spontaneous eruption of cheers signaled that something else had happened in their locker room celebration.

Turns out, Fleck announced to his team that Joe Rossi was no longer just the interim defensive coordinator. The job was his after a three-game audition.

The room burst into joyous screams. Players chanted Rossi's name and lifted him up to carry him on a victory lap around the room.

University of Minnesota
Video (00:33): After defeating Wisconsin in 2018, P.J. Fleck announced in front of the Gophers that Joe Rossi was no longer just the interim defensive coordinator.

Fleck has made hundreds of decisions in his seven-year tenure as Gophers coach. None has been more important or impactful than the one he made that day.

Defense has become a hallmark of Fleck's program ever since.

"There is a way that we play and a standard to be lived up to," Rossi said in his office this past week.

That standard is now an identity. There is an expectation that the Gophers will play stifling defense every season, regardless of personnel losses. The track record since 2019 – Rossi's first full season — reveals a consistency in high-level performance.

In that four-year window, the Gophers rank top-10 nationally in total defense, scoring defense, pass defense, rushing defense and first downs allowed.

Last season, the Gophers held eight opponents to 13 points or less. Last time that happened: 1961.

Nine Gophers defensive players have been NFL draft picks since 2019.

"The mark of a good defense is when you can have success for a sustained amount of time," Rossi said. "You're not always going to have your peak, but year in and year out, you feel confident that it's going to be done the right way."

Fleck's ball-control offensive philosophy has provided a perfect marriage with Rossi's defense. The Gophers have ranked in the top six nationally in time of possession every season since 2019, which helps keep their defense fresh. But a clock-chewing running game cannot work as effectively without a defense that holds up its end.

The Gophers ranked No. 6 nationally in third-down defense last season. They get the ball back quickly to the offense.

Fleck calls Rossi "one of the best football minds" and "one of the best teachers" he's been around in coaching and figures it's only a matter of time before a school hires him as head coach. The Gophers gave Rossi a two-year extension last December that will pay him an average of $1.15 million through 2025.

Rossi constructs his defensive structure around three core tenets: Stop the run, eliminate explosive plays, create takeaways.

He calls explosive plays the most important statistic in football because they drastically change the probability of scoring.

"People score when they get explosive plays," he said. "They struggle to score when they don't."

That area represents the most glaring improvement under Rossi following the in-season dismissal of Robb Smith in 2018. Smith's defense was one of the worst in college football at allowing big plays that season. Rossi's unit has been one of the best in limiting them.

He considers anything over 25 yards an explosive play. A quarter of the field. He sets a goal of two or fewer explosive plays per game. His defense allowed 2.31 per game last season, and 1.92 in 2021. The Gophers ranked top-six nationally in scoring defense both seasons.

"That sudden change of 25 yards," Rossi said, "makes it more times than not that you're giving up points on that drive."

He lists different factors that help limit those demoralizing plays.

Scheme: "If you are a super aggressive team, you might get more minus yardage plays," he said, "but you're probably going to give up more explosives."

Personnel: "You're never going to play good defense with below-average players," he said.

Effort: "Guys have to play really hard," he said. "If you don't play hard, it's like writing in pen. If you write in pen, you've got to be perfect."

Situational play-calling and execution of calls also play a crucial role.

Newcomers to the defense are getting indoctrinated in Rossi-isms in fall camp. Senior safety Tyler Nubin is another future NFL draft pick, but he's surrounded by some new faces, both youngsters and transfers.

Rossi doesn't blink.

"The standard doesn't change," he said. "There is an expectation."

That expectation took root when Fleck made a wise decision back in 2018.