The Big Ten Stopped Playing Defense

The Big Ten is, indisputably, one of the better power conferences in college basketball, which is to say it is better than at least three of the others. Over the last decade, it’s spent just four seasons outside KenPom’s top three conferences (2015-18, all in a row), it’s spent three of the ten years ranked as the  best conference in the whole sport, and it’s never been the worst power conference in that span. Even this year—an obvious down year—the league outranks the Big East, ACC, and Pac-12, each of whom has at least one team better than the Big Ten’s best (the Pac-12 has two). It’s a deep league, it’s a competitive league, it’s a league that’s just plain good at basketball. But this year, the defense isn’t measuring up.

Purdue is the embodiment of this. Best KenPom offense in the country, 88^th in defense, about to potentially put the fear of God into those who lean on the “it’s been ___ years since a team ranked outside the top __ in both KenPom offense and KenPom defense won the national championship” stat as ironclad law. But it isn’t just Purdue. It’s a league-wide shift. Of the six power leagues, the Big Ten ranks fifth in median defensive ranking and fourth in average defensive ranking this year. They aren’t the worst, but they’re about as bad as they’ve ever been, at least in our memory. Here it is in visual form, with the black line denoting the conference’s median defense and the gray line marking the average defense:

It’s the worst defensive year for the league in six years, and it comes on the heels of the best year for the league’s average over the whole last decade. The league, as a whole, shifted decidedly away from defense this year, intentionally or otherwise. It’s plain, simple, and easy to see.

What does this mean? In terms of the overall Big Ten, it’s mostly interesting. Defense is only half the equation, after all. It’s striking because it’s the Big Ten, and because the breadth of Big Ten football gives us this image of a defense-first league (Ohio State doesn’t really match this identity, but Ohio State isn’t exactly representative of Big Ten football as a whole). But the fact the league’s ranked third overall in KenPom is much more significant in gauging its teams’ respective quality.

It does tell us something, though, about these Big Ten teams, and specifically about Purdue, who is now the only Big Ten team left.

Purdue hasn’t faced many good defenses this year. It’s faced Indiana’s twice, and Illinois’s twice, and Villanova’s once and Texas’s now once, but every other defense on the schedule grades out today as worse than that of Saint Peter’s, their opponent tonight. They also aren’t used to facing strong defensive teams with regularity. This will be just the second time this year they’ve faced consecutive defenses of the caliber of that of Saint Peter’s, and if both UCLA and Purdue should win, Sunday would mark Purdue’s first stint of playing three such opponents in a row.

Again, defense is only half the game. But for as much of a dangerous-buy-game as this appears to be on paper, there’s an element here belonging more strongly to conference play—the element where the Peacocks are going to offer the Boilermakers a single, notably difficult test. At times (against Illinois, Villanova, and Texas), Purdue’s thrived against such opposition. At times (against Indiana, even in the win), Purdue’s wilted. We might look back on it as meaningless, or close to it. But Purdue has its work cut out for it tonight. The Big Ten is not what we’re used to it being.