What to expect from Duke's talented freshmen on defense

Williamson, Barrett among 2019 NBA draft prospects to watch (1:29)

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Ever since Mike Krzyzewski started relying heavily on one-and-done players about five years ago, we've grown accustomed to praising the Blue Devils' offense but doubting their defense. Annually.

It's an easy habit to fall into, one that fits comfortably with our preconceived notions of how college basketball should work. Sure, we tell ourselves, these amazing freshmen are talented, but they'll never last in the NCAA tournament unless they commit to playing defense the way Duke's 2015 national title team eventually did.

But a funny thing happened to this annual habit last season. Yet another very young Duke team took the floor, only this one played very good defense, about as good as the 2015 title team, actually.

Yet here we are again in the 2018-19 preseason, conceding that the Blue Devils will have amazing talent but wondering, as always, whether all these NBA-track freshmen will buckle down and play defense.

Do we wonder just out of habit, or is there a solid basketball rationale behind this questioning? Here are four thoughts offered in the hopes that they may help us make sense of the Duke defense in 2018-19.