DARI (Deterrence-Adjusted Rim Impact)
A better way to measure rim protection.
DARI is my attempt to answer one of the hardest questions in college basketball analytics: who actually protects the rim best?
Traditional stats like blocks and block rate only tell a small part of the story. Great rim protectors don’t just block shots — they change offensive behavior entirely. They make guards hesitate, force jumpers and floaters instead of layups, and convince teams not to attack the basket at all. This makes rim protection especially difficult to measure, because the best plays often never happen.
A guard sees a dominant shot blocker waiting, tip toes around the baseline, and kicks the ball back out. There’s no block, no rebound, and sometimes no stat at all, but the defense still won that segment of the possession. Conversely, a bad rim defender may get attacked frequently, leading to a large quantity of blocks, but even more buckets for the opponents.
DARI is built to measure that full impact.
What Is DARI?
DARI stands for Deterrence-Adjusted Rim Impact. It evaluates how much a player affects opponent efficiency at the rim while accounting for context. The model looks beyond the traditional box score using on/off individual and team stats to capture three major pieces of rim defense:
Shot deterrence: Are opponents avoiding the basket more often when this player is on the floor?
Rim accuracy suppression: When teams do attack, are they finishing worse than expected?
Foul-avoidance: Is the defender hurting his team by committing too many fouls in his attempts to protect the rim?
Plus defensive environment adjustments: How much help or difficulty comes from teammates, scheme, opponents, and schedule strength?
One of the biggest problems in evaluating defense is separating individual impact from team impact. A center playing behind elite perimeter defenders may face fewer difficult situations, while another big man might constantly clean up broken plays. DARI attempts to isolate the player from the ecosystem around him to the best we can do in a limited sample college basketball environment without tracking data. DARI applies adjustments to every player based on his coach’s historical baseline of FG% allowed at the rim, as well as adjusting for strength of opponents. Deterrence is calculated compared to when the player is off the floor, adjusting for the quality of backups.
The results tend to align with what fans see on film from elite college bigs: the best defenders anchor entire schemes, erase mistakes from teammates, and fundamentally alter how opponents want to play. But the model also helps uncover underrated players on smaller stages whose impact may not show up in national conversations.
No defensive metric is perfect, especially in a sport as interconnected as basketball. But DARI aims to move closer to measuring rim protection the way coaches and scouts actually think about it: not just by counting blocks, but by understanding who truly controls the paint.
2026 Best Rim Protectors
Here’s the top 20 big men in DARI for the ‘25-26 season. I’ve included raw deterrence, contest quality, and foul factors in the chart as well. These do not add up to the total DARI due to various adjustments, but they are instructive in which parts of rim protection the players shine. There are defensive players of the year from the A10, Big Ten, and Big East all in the top 4. Other noteworthy rim protectors like Mo Krivas and Sean Logan are here as well.
Best DARI “All-Time” (Last 4 Seasons)
If we zoom out a bit, we can look at the best overall seasons in the last 4 years, from ‘22-’23 to ‘25-’26. Ryan Kalkbrenner had by far the best rim protection season with his ‘24 campaign. As measured by traditional and even advanced box score stats, we’d consider him to be a good rim protector (7.6% block rate). But that doesn’t do his actual impact justice. His deterrence grades out massively, turning away a ton of rim attempts from even happening, as well as holding opponents to 49.5% at the rim when they did attempt shots. All while essentially never fouling.
Justice Ajogbor of Saint Joseph’s had two of the 4 best seasons in the sample. Also, both of Donovan Clingan’s seasons in college rank in the top 15, while Ryan Kalkbrenner’s 2nd best season ranks just outside at #21. Jamarion Sharp also had two seasons in the top 20. Aday Mara’s ‘26 season still ranks in the top 10 overall.
Coach Scheme Effects
In the development of this metric, I isolated the at rim FG% defense numbers for teams during a 5-year period. I attributed those to the coaches to create a baseline expectation (modifying the effect on the metric for coaches with less years in the sample). But I found these rim % numbers to be interesting on their own, so I’m presenting some of the data here. Here are the top 10 and bottom 10 coaches, of those that coached with one team for the entirety of the 5-year sample. Division 1 median FG% at the rim was 58.1%.
And the bottom 10:
There is a circular relationship with coaches/schemes and their personnel. Coaches that prioritize rim defense recruit good rim protectors, but they also scheme in ways and preach rotations and positioning to develop those players and maximize their skills even further. On the other hand, there are coaches with successful defenses in the bottom 10 as well. Coaches who either prioritize deterrence (like Matt Painter) or turnovers/disruption (like T.J. Otzelberger).
Data
Get the full list of qualified players from the last 4 seasons and their DARI scores here:
https://dari-explorer.streamlit.app/