Team Defense

A team’s defense can be evaluated using the same 7 stats:

  1. 3P%: opponent’s 3-point field goal percentage
  2. 2P%: opponent’s 2-point field goal percentage
  3. FT%: opponent’s free throw percentage
  4. Blk%: opponent’s block percentage
  5. St%: opponent’s steal percentage
  6. A%: opponent’s assist percentage
  7. 3PA%: opponent’s 3-point attempt percentage

3P%

A team’s defensive 3-point field goal percentage is its opponents’ made 3-point shots divided by its opponents’ attempted 3-point shots.

3P% = Opp. 3PM / Opp. 3PA * 100

Houston’s defensive 3P% was 26.9% in the 2018-2019 season, good for 1st amongst all Division-I teams.

Its opponents made 233 3-point shots in 866 attempts.

3P% = 233 / 866 * 100 = 26.9%

For a comparison, Denver’s opponents made 41.8% of their 3-point shots. That’s good for 353rd in the country in the 2018-2019 season.

KenPom has written extensively about why a team’s 3P% defense should not be defined by its opponent’s 3P% offense.

2P%

A team’s defensive 2-point field goal percentage is calculated by taking its opponents’ 2-point makes and dividing them by its opponents’ 2-point attempts.

2P% = Opp. 2PM / Opp. 2PA * 100

UC Irvine ranked 1st in the nation limiting opponents’ 2P% to 40.5% in the 2018-19 season.

UC Irvine opponents made 568 of 1403 2-point shot attempts.

2P% = 568 / 1403 * 100 = 40.5%

For some contrast, Iowa’s opponents made 53.5% of its 2-point shots. That clip was 299th amongst all Division-I teams.

While 3P% is not indicative of a team’s 3-point defense, 2P% can be attributed some to how a team protects the rim and defends overall.

FT%

A team’s defensive free throw percentage is its opponent’s free throw makes divided by its opponents’ free throw attempts.

FT% = FTM / FTA * 100

UCF opponents made 65.0% of its free throws in the 2018-2019 season. This percentage put the Golden Knights at 3rd in the country.

And in comparison, North Dakota opponents made 78.6% of their free throw attempts. This was rated last or 353rd out of all teams in 2018-2019.

Obviously you can’t defend free throws. It’s an uncontested shot. But if you can limit a team from attempting free throws, it could be a big factor. Can’t make them if you don’t take them.

Blk%

Defensive Block percentage is a team’s total blocked shots divided by its opponents’ 2-point field goal attempts.

Blk% = Blocked shots / Opp. 2PA * 100

Duke ranked 3rd in the country blocking 16.4% of its opponents’ 2-point shot attempts.

The Blue Devils blocked 257 of its opponents’ 1571 shot attempts.

Blk = 257 / 1571 * 100 = 16.4%

Northeastern blocked only 6.0% of its opponents’ shots in 2018-2019. This clip ranked 322nd in the country.

Stl%

A team’s defensive steals percentage is a team’s total number of steals divided by its opponent’s offensive possessions.

Stls% = Total steals / Possessions

Washington posted a 13.3% steals percentage in 2018-2019. This was good for 1st in the country.

The Huskies recorded 323 steals in its opponents’ estimated 2,430 offensive possessions.

Stls% = 294 / 2,430 * 100 = 13.3%

In comparison, Winthrop’s defensive steal percentage was more than half of that at 5.4%. This ranked last in the country.

A%

A team’s defensive assist percentage is its opponents’ total amount of assists divided by its opponents’ made field goals. This includes both 3-point and 2-point makes.

A% = Opp. assists / Opp. FGM * 100

New Mexico State ranked 1st amongst all Division-I teams limiting its opponents to a 39.2% assist percentage. New Mexico State’s opponents had 309 assists on 789 made baskets.

A% = 309 / 789 * 100 = 39.2%

Syracuse opponents registered a 67.8% assist percentage in the 2018-2019 season. This was almost dead last (352nd) amongst all teams.

Assist percentage sometimes has less do with defense, and more to do with style of play. Syracuse is known for its 2-3 zone, and to beat a zone, you must share the ball.

3PA%

A team’s defensive 3-point attempt percentage is the percentage of 3-point shots its opponents attempt divided by their opponents’ total shot attempts.

3PA% = Opp. 3PA / Opp. FGA * 100

Stanford’s opponents took 27.3% of their shots from behind the 3-point line in the 2018-2019 season. This was 1st amongst all Division-I teams.

The Cardinals opponents’ attempted 515 3-pointers out of 1,886 total shot attempts.

3PA% = 515 / 1886 * 100 = 27.3%

In contrast, Virginia Tech’s opponents attempted 49.9% of their shots from behind the 3-point line. That’s percentage ranked 352nd in the country.

Remember: Teams have much more control over how many 3-point shots their opponents shoot than how many they make.