How NBA offenses became impossible to defend

We’re witnessing an offensive explosion unlike any in NBA history. The average offensive efficiency for an NBA team — points scored per 100 possessions — reached its highest points ever in each of the last two seasons. The league’s best defense this year, the Boston Celtics, would have ranked 14th in points allowed per 100 possessions 20 years ago.

Why is this happening? One word: space. (And one word it’s definitely not: effort).

Thanks to improvements in three-point shooting, NBA teams are using more of the court than ever before. Consider the two screenshots below. One is from a 1988 playoff game. The other is a Timberwolves offensive possession from mid-February.

(The Timberwolves, by the way, averaged the fewest three-point attempts in the NBA this year).

What happens when you increase the playing surface that much without adding more defenders to fill it? The defense gets stretched like a rubber band snapping.

That just means more space for great penetrators to collapse a defense that must travel from further away to collapse. And when that happens, all sorts of goodies open up for offenses.

One potential antidote to this is switching. At least that in theory keeps the ball in front of you and prevents the nuclear scenario of a collapse.

Problem is, then you’re leaving a lesser defender on an island against a great scorer, with more room than ever to attack. And if they can hit stepback threes the way so many do now, what is a defense to do?

Try as it might, not much. The defenses aren’t failing due to a lack of effort. They’re failing because they have too much ground for any five humans to cover.