It was bound to happen.
As great as this star-studded Duke team has looked this season, there were flashes of vulnerability in each of the Blue Devils' most impressive wins (with comeback efforts against Michigan State, Texas and Florida) before Saturday's shocker.
Boston College's 89-84 upset in the ACC opener was a product of an inspired effort and lights-out shooting performance against the nation's top-ranked team, but it also seemed inevitable — because of the Blue Devils' youth and spotty defense.
This edition of the Blue Devils was never going to go undefeated, and that's because as talented as national player of the year candidate Marvin Bagley III is and as strong of a leader as Grayson Allen has become, identifying Duke's problem wasn't difficult. The Blue Devils (11-1) simply are not there defensively — particularly as a unit. So all it took was a nicely crafted game plan and brilliant shooting to expose that.
Before Saturday, Duke ranked in the 200s nationally in scoring defense and three-point field-goal percentage defense (B.C. shot 15-for-26 from three compared with Duke's 8-for-30). In Saturday's case against B.C., it was awful perimeter defending (closing out, making it difficult from three-point range) and discombobulated defense against the pick-and-roll.
Coach Jim Christian exposed Duke's athletic big men with an arsenal of ball picks, isolating them on switches against quicker guards, namely Ky Bowman, who carved through defenders to finish with 30 points and was one assist shy of a triple-double. Bowman and his two backcourt mates, Jerome Robinson and Jordan Chatman, each had five three-pointers, and the trio of guards combined for 74 of the Eagles' 89 points.
Boston College clearly illustrated the type of punch that Duke will to counter come March. And that's part of the beauty of December and January games: They give talented teams the opportunity to lose and learn.
Duke is extremely talented and will be fine. If anything this is a good wakeup call. But coach Mike Krzyzewski has fixes to make. And they start with a youthful roster that is playing to its age defensively.