How Illinois Basketball Can Slow Down Duke Freshman Cooper Flagg

There's no perfect solution, but the Illini at least have a rough blueprint they can follow to give Flagg pause

Feb 17, 2025; Charlottesville, Virginia, USA; Duke Blue Devils guard Cooper Flagg (2) stands on the court against the Virginia Cavaliers in the second half at John Paul Jones Arena. Mandatory Credit: Geoff Burke-Imagn Images | Geoff Burke-Imagn Images

It's a question that every Duke opponent has asked this season and literally none has found the answer to: How to slow down Blue Devils freshman Cooper Flagg?

Flagg, averaging 19.7 points, 7.7 rebounds and 4.0 assists on the season, is a springy, 6-foot-9 seemingly unstoppable force. The Duke opponents this season that have had the most luck in holding down Flagg's numbers have, quite inadvertently, forced the freshman off the floor early by getting pummeled and convincing Blue Devils coach Jon Scheyer to hand the reins over to the second unit.

That won't do for Illinois (17-10) when it meets No. 3 Duke (23-3) on Saturday at New York City's Madison Square Garden. So what's the move?

The Illini don't have a ready-out-of-the-box Flagg stopper on the roster, and their defense is down a man in Morez Johnson Jr. (broken wrist). Even if the remaining Illinois players are healthy – and that is by no means a certainty given Tomislav Ivisic's recent ankle sprain and a rampant flu bug – any single defender checking Flagg is likely to have the effect of throwing a wet blanket on a house fire.

Instead, expect Illini coach Brad Underwood to deploy a strategy similar to the one he followed against Minnesota's Dawson Garcia. At 6-foot-11, Garcia is a couple inches taller than, but not as explosive or powerful as, Flagg. But his all-court game is similar enough to make him a reasonable comp.

Illinois took the kitchen-sink approach against Garcia, throwing a variety of defenders at him, shadowing and contesting on the perimeter and sending frequent help and double teams when Garcia touched the ball near the paint.

There are some distinct differences in this matchup, both favorable and unfavorable, for Illinois. First, the bad: Flagg's supporting cast is exceptional, and Flagg is a better playmaker than Garcia. If the Illini send extra help against Flagg and are slow in their rotations, they're toast. On the other hand, the athletic, 6-foot-7 Tre White – who played less than a minute in the Gophers game earlier this month – will be available Saturday. He is the closest thing Illinois has to a matchup defender to check Flagg.

The Illini should accept that Flagg is going to get ding them, yet make him work for everything: Sprint with him in transition. Run him off the three-point line. Challenge him at the rim. Ben Humrichous (6-foot-9), Will Riley (6-foot-8) and Kylan Boswell (6-foot-2) all bring different defensive profiles to the matchup, but small doses of each as a change of pace to White may at least force Flagg to think, adjust and perhaps make an occasional mistake or lose a fraction of reaction time.

It may not be much, but it's likely the best the Illini can hope for.

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