What is Defensive Rating?
Defensive rating (DRTG) is the number of points a team or player allows per 100 possessions — a possession-adjusted measure that's considered the most accurate single statistic for evaluating defensive effectiveness in basketball.
Defensive rating (DRTG) is an advanced basketball statistic that measures how many points a team or player allows per 100 possessions. By adjusting for pace — the number of possessions a team uses per game — DRTG allows fair comparisons between teams and players regardless of playing style or era.
Defensive rating, along with offensive rating, is foundational to modern basketball analytics and is widely used by NBA front offices, coaches, and analysts to evaluate defensive performance.
Team Defensive Rating
Team DRTG answers a simple question: for every 100 possessions the opponent has, how many points do they score?
$$\text{Defensive Rating} = \frac{\text{Points Allowed}}{\text{Possessions}} \times 100$$
Since an average NBA team scores about 110–115 points per 100 possessions, a team defensive rating in that range is league-average. Lower is better on defense.
NBA Defensive Rating Context (approximate ranges)
| DRTG | Interpretation |
|---|---|
| Below 107 | Elite defense — typically top 3–5 in the league |
| 107–110 | Above average |
| 110–113 | Average |
| 113–116 | Below average |
| Above 116 | Poor defense |
Championship-caliber teams typically rank in the top half of the league in both defensive rating and offensive rating. The most dominant defensive teams in recent NBA history have posted defensive ratings below 104.
Player Defensive Rating
Individual DRTG measures how many points per 100 possessions the opponent scores while a specific player is on the court. It's calculated differently than team DRTG and involves complex adjustments — because basketball defense is inherently collaborative, a player who guards the opponent's worst offensive player every night can appear to have a great individual defensive rating without being a great defender.
Player defensive rating is therefore best interpreted in combination with other defensive metrics:
- Defensive Win Shares (DWS) — Estimates how many wins a player contributed on defense
- DPOY voting — Defensive Player of the Year consideration reflects collective scouting judgment
- On/off splits — How the team's defense changes with a player on vs. off the court
- Opponent shooting percentage — How opponents shoot when guarded by a specific player (available from tracking data)
Defensive Rating vs. Points Per Game Allowed
Older defensive statistics (points allowed per game) were problematic because they didn't account for pace. A team that plays fast and generates 100 possessions per game will allow more total points than a team playing 90 possessions per game — but might actually be the better defensive team on a per-possession basis.
DRTG solves this problem by normalizing everything to 100 possessions, making cross-team and cross-era comparisons meaningful.
Net Rating
Net rating is the difference between a team's offensive rating and defensive rating:
$$\text{Net Rating} = \text{Offensive Rating} - \text{Defensive Rating}$$
A team with a +5 net rating scores 5 more points per 100 possessions than it allows. Net rating is one of the strongest predictors of regular-season success and playoff outcomes — historically more predictive than win-loss record, especially for identifying teams that are better or worse than their record suggests.
Defensive Rating in Practice
When evaluating a team's defense, analysts typically look at:
- Half-court defensive rating vs. transition defensive rating separately — some teams are great in the half court but give up too many fast break points
- Home vs. away splits — Some teams' defenses benefit significantly from home-court noise
- Defensive rating against specific shot types — How well does the team defend three-pointers vs. the paint?
Understanding defensive rating gives you a far richer picture of how good a defense actually is than traditional stats like blocks and steals ever could.