As the season has progressed, the San Antonio Spurs’ defense has improved. At the end of November, they ranked 12th overall in defensive rating at 102.4 points per 100 possessions. By the end of the 2016, they had improved to 4th, with a defensive rating of 101.4 Pp/100. Currently, they sit atop the league at 100.8 Pp/100. While much of this rise can be attributed to other teams that were ranked higher regressing, the Spurs have certainly contributed to their rise in the rankings as well.
The Spurs’ defense shines in limiting opponents’ offensive weapons. Per 100 possessions, teams are only attempting 24.7 threes against the Spurs, fourth lowest in the league. Better still, opponents are only making 8.4 of those attempts, second lowest in the league. Threes have become a centerpiece for many modern offenses. When teams are hitting threes, it often creates space for more off-ball movement, feeding offense in the paint and other easy shots. When teams are not shooting or hitting threes as often, it gives every defender more leeway. Since the offense is forced to create shots inside the perimeter, help defenders will generally be closer.
The Spurs are also 9th best in opponent’s free throws attempted per 100 possessions at 22.2. Limiting free throws is important for several key reasons. First, free throws are incredibly accurate. No team is averaging under 70% on free throw attempts, meaning that possessions that include two free throws result in at least 1.40 points-per-possession on average for teams, at worst. For reference, the league’s best offense, currently owned by the Golden State Warriors, scores about 1.13 points-per-possession. It also gives the teams shooting the free throws a better chance to set up on defense afterwards, rather than off of a field goal make, where a player could leak out in transition early and attack the defense before it is set.
The Spurs force turnovers as well. Per 100 possessions, the Spurs force 14.9 turnovers, 10th best in the league. While 10th may not seem impressive, only .6 turnovers per 100 possessions separate them from 2nd, whereas 1.4 turnovers separates them from 20th. On average, only 85.1 possessions out of 100 even have the possibility in resulting in points for Spurs’ opponents.
Looking at the ways that the Spurs’ defense limits opposing teams, it becomes clear why it is so effective: the Spurs just make scoring hard for many teams. These strengths will be important in the playoffs where several contenders rely on either threes or free throws (or in the case of the Houston Rockets, both) for large portions of their offense.
Stats obtained from nba.com/stats