Last Saturday, Joe Rossi sat in the coaches box and did something he hadn’t in nearly three years. He ran a defense during a game.

The result: The Gophers, who had given up 55 points and 646 yards the week before, routed Purdue 41-10, not allowing a touchdown until the final 5½ minutes. They held the Boilermakers to 233 yards and left them 0-for-12 on third-down conversion attempts.

So, whatcha gonna do for an encore, Coach?

“Guys, let’s not bank on oh-fers every week,’’ Rossi, the interim defensive coordinator, said Wednesday. “Those don’t happen very often.’’

Rossi’s coordinating debut for the Gophers last week was his first time running a defense since 2015, his final year as Rutgers’ defensive coordinator. He replaced the fired Robb Smith and immediately delivered, though he was quick to give his players all the credit.

“Guys had fun. Guys played hard. Guys swarmed to the ball,’’ Rossi said. “I was excited for the guys to be able to go out and have a performance like that. They deserve the credit with how they performed during the week, but just being able to go out and execute and communicate. … Just seeing them flying around and having fun was exciting.’’

That energy was especially apparent with the linebackers, a position group of which Rossi is now in charge. Senior Blake Cashman led the team with nine tackles, had a half-sack, made a fourth-down tackle for no gain and forced and returned a fumble 40 yards for a touchdown. Junior Thomas Barber had eight tackles and 1½ sacks. In the loss at Illinois, they combined for only five tackles.

“They felt like [they] didn’t have their best game the week before and said, ‘We need to play better,’ ’’ Rossi said. “We talked about it as a defense. If you want to play better, how do you play better? Well, you prepare better, you practice better, you study film more. We felt like going into the game, they had confidence. And when you have confidence going into the game, it allows you to go out and play fast.’’

The Gophers (5-5, 2-5 Big Ten) will try to use that approach again Saturday, when Big Ten West Division champion Northwestern visits TCF Bank Stadium. The Wildcats (6-4, 6-1) have been ground-heavy as of late, rushing for 184 yards in a 14-10 win at Iowa last week and 182 in a 31-17 win over Wisconsin on Oct. 27. Rossi, however, expects Northwestern to show balance.

“They have versatility, they spread the ball around and get it to a lot of different receivers,’’ he said. “The quarterback has a lot of experience. He can make all the throws.’’

Rossi sees a lively defense that’s engaged in the task of building on last week’s performance.

“I was very impressed with practice today, just because of the communication and excitement level,’’ he said.

“Guys were flying around today, they were talking. When a defense talks, it usually means they’re confident. And when they’re confident, you’ve got a shot.’’