Why Defense is Biggest Concern for Blue Devils

The Duke Blue Devils picked up another ACC win over Louisville. That was an impressive win as they needed a second-half surge to get it done. But it is also a win that they need to go and look back on and see what they can improve.

The biggest concern for this team right now is on the defensive end of the floor. Duke has not played a good defensive game over the last couple of times out. That does not seem huge because they are winning. But that could cause them a lot of problems down the stretch. That is something they want to fix now before it is too late.

Louisville Cardinals guard J'vonne Hadley (1) tries to drive around Duke Blue Devils forward Cameron Boozer (12) in the loss against Duke Blue during ACC play January 6, 2026. | Matt Stone/Courier Journal / USA TODAY NETWORK via Imagn Images

Duke Defensive Problems

"Duke was the No. 4 defense in America through the first 10 games of the season, holding Kansas, Arkansas, Florida, Texas and Michigan State under wraps with excellent team defense," said Issac Trotter of CBS Sports.

But the No. 6 Blue Devils have eroded lately on that end. Texas Tech (1.16 points per possession), Georgia Tech (1.09 points per possession) and most recently, Florida State (1.24 points per possession) have eviscerated a Duke defense that has now dropped to 16th nationally in effectiveness.

Jan 6, 2026; Louisville, Kentucky, USA; Duke Blue Devils head coach Jon Scheyer talks with Duke Blue Devils guard Isaiah Evans (3) during the first half against the Louisville Cardinals at KFC Yum! Center. Duke defeated Louisville 84-73. Mandatory Credit: Jamie Rhodes-Imagn Images | Jamie Rhodes-Imagn Images

The Florida State showing was the third-worst defensive game of the Jon Scheyer era. Duke's coach has vowed to get it fixed, but there's a good chance that Duke is closer to the 16th-best defense, not the 4th-best in America.

Florida State's pace-and-space gameplan stretched Duke out a bit and highlighted that the Blue Devils just don't quite the same defensive personnel on that end as a year ago.

Going from Tyrese Proctor to Caleb Foster is probably a wash defensively.
Going from Kon Knueppel to Isaiah Evans is a slight downgrade defensively.
Going from Sion James to Cayden Boozer is a real downgrade defensively.
Going from Cooper Flagg to Cameron Boozer is a real downgrade defensively.
Going from Khaman Maluach to Patrick Ngongba is a slight downgrade defensively overall, even though Ngongba's defensive processing and rim protection has been encouraging lately.

Dec 31, 2025; Durham, North Carolina, USA; Duke Blue Devils head coach Jon Scheyer (right) and assistant coach Chris Carrawell direct players during the second half against the Georgia Tech Yellow Jackets at Cameron Indoor Stadium. The Blue Devils won 85-79. Mandatory Credit: Rob Kinnan-Imagn Images | Rob Kinnan-Imagn Images

Duke's team defense has to be more connected, like it was in the early going, because it doesn't have the ridiculous defensive personnel that it enjoyed last year.

This team has the ability to do something special this season. They know that it has to come on the defensive end of the floor for them to make a run and win it all. That is something head coach Jon Scheyer has been preaching to his team since the season started. Now they will go back to look and see how they could get better on defense.

wcw — Dec 31, 2025; Durham, North Carolina, USA; Duke Blue Devils head coach Jon Scheyer (right) talks to guards Cayden Boozer (2) and Isaiah Evans (3) during the second half against the Georgia Tech Yellow Jackets at Cameron Indoor Stadium. The Blue Devils won 85-79. Mandatory Credit: Rob Kinnan-Imagn Images | Rob Kinnan-Imagn Images

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