Kyler Brown and Duke D have found motivation from his brother, Kelby

This was supposed to be the year Kelby and Kyler Brown started together, two brothers ready to help the Duke defense play at its highest level yet.

But when Kelby Brown went down with another season-ending knee injury before camp even started, questions from the outside world crept in. With only one starter returning between the defensive line and linebackers, how would the Blue Devils cope without their best player?

It turns out, they would just morph into individual Kelby Browns. At least, it seems that way watching Duke play defense this year in a way that is reminiscent of the way Kelby Brown played: physical, aggressive, relentless and determined with an all-out intensity that has not been seen around Durham -- maybe ever.

“Kelby’s a great role model when it comes to all that, and I don’t know if it’s necessarily because we’re all trying to get Kelby’s back, but for sure we’re showing his attributes,” said Kyler Brown, a starting defensive end. “I think it’s pretty contagious once you see somebody doing it, you’re more likely to do it, give 100 percent and get excited for every play. That’s helped create a domino effect.”

Though Kelby Brown cannot play, he has been able to help influence his teammates as a student assistant coach. He remains as committed to Duke as when he was starring in the middle of the defense.

“Kelby’s prints are all over it,” coach David Cutcliffe said. “Certainly Jim Knowles has done a great job with some really inexperienced linebackers himself. But Kelby is with those guys and studies tape with them, and it's helping them on the field, and that's made a difference.”

As for the personality the team has developed, Kyler Brown and A.J. Wolf said there was a change in mind-set during spring practice, when coaches and players decided to play more physical up front. They changed some of the way they approached blocking linemen. Players pushed each other to do more reps in the weight room, or to lift a few extra pounds.

The results have been obvious. Duke ranks No. 9 in the nation in total defense, giving up an average of 269.8 yards per game. The last time Duke gave up less than 300 yards of offense over the course of a season was in 1973. The Blue Devils also rank No. 5 in scoring defense (10.6 points per game) and are giving up an average of 123.4 yards rushing per game. That’s after playing Georgia Tech.

If they continue this pace, Duke would put up the best numbers in all three categories under Cutcliffe.

“Way back last spring, we came in knowing we wanted to try to dominate and be really physical, be really aggressive and have an attack mentality instead of a wait and see,” defensive tackle A.J. Wolf said. “Just get off the ball, play physical, play as hard as you can and that’s how you’re going to make plays. You have to fit with the defense, but being reckless out there, that’s been the primary thing.”

With five new starters between the linemen and linebackers, the projections about the Duke defense were not exactly stellar going into the season. ESPN’s FPI, for example, projected Duke would finish with the worst defense in the ACC.

Though Duke didn’t have many starters coming back, many of those guys had game experience. And that, along with the new mentality, has helped the Blue Devils become a revelation -- to those outside their football facility, anyway.

“There were a lot of implications that we wouldn’t be as good but we knew as a unit that definitely was not going to be true,” Wolf said. “Even though we didn’t start games, we’ve been playing college football for three or four years, practicing and working really hard. We knew we were going to be really good this year. We had no doubts even though the media did.”