GREEN BAY – The Packers’ success on defense can be traced back to one move: Clay Matthews from outside linebacker to inside linebacker midway through last season.

Why has it made such an impact?

“Your goal is to try to get your best 11 football players on the field. Obviously, we had more depth at outside linebacker than we did at inside linebacker,” Defensive Coordinator Dom Capers said on Monday, following one of the best defensive performances by the Packers in recent memory.

“He’s a unique guy. I’ve always felt he’d be a Pro Bowl inside or Pro Bowl outside linebacker,” Capers said of Matthews. “Our job is to figure out what it’s going to take to win a game.”

Matthews was the dominant force in Sunday’s win at Levi’s Stadium. He was credited with a sack, two tackles for loss and two hurries, but his main contribution was stopping quarterback Colin Kaepernick from doing to the Packers on Sunday what he had done to the Packers in the three previous outings between the two teams. Sunday, Matthews shadowed Kaepernick and helped hold him to 57 yards rushing.

One move has made all the difference. One move at midseason last year turned the Packers into a complete football team, and that move has the Packers moving up the league defense rankings. The Packers are No. 8 in total defense, two spots higher than the Packers offense.

“Our play style was excellent. You’re always concerned about a short week going to the West Coast. Our goal going into a game is always to not let a team cross the goal line. I was pleased with the red zone defense,” Capers said.

“We had a lot of respect for (Carlos) Hyde. If you stop the run early, teams will get impatient. That allowed us to dictate a little more in the down and distance and get after Kaepernick. By stopping the run, we won a high percentage of the downs on first down,” Capers added.

The surprise is the Packers defense has gotten so good so quickly.

“I’ve always felt with the number of young guys we have, if they stay tuned in we’d get better. I’m encouraged because we have a variety of guys playing,” Capers said.

New stars are emerging. Nick Perry has three sacks. Jayrone Elliott has two. They represent the young depth at outside linebacker to which Capers referred. It has allowed a complete makeover at inside linebacker.

“By moving Clay inside, it’s given those guys more playing time outside,” Capers said.

Everything has seemingly improved since Matthews moved inside.