An Overview of Bob Kloppenburg's SOS Pressure Defense

By Dr. James Gels, From the Coach’s Clipboard Basketball Playbook
"Helping coaches coach better..."

s This article is the first in three part series on Bob Kloppenburg's SOS pressure defense, by permission from Coach Kloppenburg.

Bob was a great high school and college player years ago, and became a high school coach. He went on to coach very successfully at the college level for 22 years at Cal Western, with a tremendous winning record and a number of trips to the NAIA national tournament. He has coached at the professional level with the Seattle Supersonics, and also with the Rockets, Nuggets, Raptors, Bobcats, and Clippers.

Bob has developed and tweaked his SOS defense for over 50 years. His SOS Defense has been used by high school and college teams around the world. In the USA, he has conducted over 20 SOS clinics, as well as clinics for basketball federations in 14 other countries.

"Bob Kloppenburg is a defensive genius." - Pat Riley, NBA Coach Retired

Bob Kloppenburg
Bob Kloppenburg


What is the SOS Defense?

This is a basic introduction and overview of the SOS defense. Rather than reinventing the wheel, where diagrams and details are necessary, I have simply provided a link to Coach Kloppenburg's website. Any coach or player who wants to learn more and implement the SOS system will definitely want to purchase Coach Kloppenburg's DVDs, books or ebook (see below).

The SOS Pressure Defensive system is based on the concept of total disruption. The defense is proactive and attacks the offense, forcing offensive players into uncomfortable positions on the court, where scoring is difficult. Instead of the defense reacting to what the offense is doing, the offense finds themselves reacting more to the defense than vice-versa. The SOS defense stops scorers, decreases second shot chances, and dictates the game tempo. You can generate a lot of "offense off defense" with the SOS.

Implementing SOS Tactics

In implementing the SOS tactics, Coach Kloppenburg puts it in perspective. If you already have a pretty good defensive system, rather than completely changing it, just add those SOS tactics that you think might help within the framework of your own defense.

On the other hand, if your current defense is not very good and you want a complete overhaul, then go full force into the entire SOS system.


Six Keys of the SOS System

Key #1 - Fundamental Player Defensive Skills are Taught in a Simple to More Complex Progression

No defensive system will work if your players are not skilled in defensive fundamentals, both on and off the ball. And no system will work if players are not motivated to play great defense. You have to make it a priority, instilling enthusiasm, a work ethic, and pride in playing great defense.

The teaching breakdown begins with 1-on-1 techniques and drills, progressing to 2-on-2, and up through 5-on-5. When first introducing drills, it takes a little longer, with important focus on details and doing things correctly. Subsequently, quick, short "reinforcement" drills are done every day to continue to sharpen and make the necessary skills automatic.

Key #2 - Communication - Key S-O-S Words Identify and Trigger Defensive Actions

Coach Kloppenburg stresses certain key words for defensive communication. Each key word begins with one of the S-O-S letters. Just like the commonly used defensive terms of "ball", "deny" and "help", so it is with the SOS key words. They help players communicate and work together as a unit. Talking is stressed in practice and games.

On-ball defensive keywords are "Set", "On", and "Smother". "Set" refers to the specific body stance and movement required to force the ball handler to put the ball on the floor rather than to shoot or pass. "On" refers to a body position that the defender assumes when guarding and forcefully guiding a dribbler to a checkpoint. "Smother" is the "in your face" stance and movement used to put maximum pressure on the ball handler attempting to shoot or pass.

Off-ball keywords are "Snuggle", "Off" and "Strike". For switching screens, "Screen", "Over", and "Switch" are keywords.

Key #3 - Defenders Force Offensive Players to Specific Checkpoint Areas on the Court

Forcing opponents into uncomfortable areas of the court (where scoring opportunities are poor) is a main key of the SOS defense. Coach Kloppenburg calls this "Operation Checkpoint". Defenders are taught how to direct the offensive player away from high percentage scoring areas to low percentage "checkpoint" areas.

Key #4 - Switching 2-on-2 Screens

Aggressive switching of on-ball and off-ball screens is an important aspect of this tough, pressure defense. Switching helps eliminate confusion and defensive hesitation and when done correctly and aggressively, can frustrate and force the offense away from what they originally intended to do. Keywords "Screen", "Over", and "Switch" are used.

Coaches often debate how to best defend screens. Some simply will never switch, not wanting mis-matches. Coach Kloppenburg has been around a long time, at every level, and has seen what works best most of the time. He teaches automatic "contact switching" on all on-ball and off-ball screens, and presents very solid reasons for this.

Key #5 - Stopping the Fast Break Begins in the Backcourt

To stop an opponent's aggressive transition, fast-breaking offense, coaches stress "get back on defense!" Yes that's important, but Coach Kloppenburg also wants to start pressure in the backcourt by getting to the outlet pass, and stopping or forcing the dribbler to a checkpoint area, while other defenders sprint up and deny the long passing lanes up the court. Start working the offense right away... don't let them be the aggressor.

He also discusses full-court presses ("Basic Shadow", "Shadow Up", "Shadow Face", "Shadow Blitz" and "Shadow Lock") and half-court presses ("X" and "Red" presses).

Key #6 - Each Defender has a Clear-Cut Specific Role

The SOS system is truly a "team defense", not just five individuals. All are communicating and working together. Each player has a specific role and must follow the rules and rotations. Little is left to chance as all the possible scenarios are covered.

The entire team takes on the enthusiasm of playing nasty, tough defense, working together like a machine, forcing the offense out of their comfort areas. Success breeds excitement and pride in your system, pride in playing tough defense. Tough defense frustrates and annoys the hell out of opponents.

Tough defense is what leads to upsets. Your team may not be a an offensive powerhouse, but it's not so bad if the opponent can't score either! Underdogs take heart... the SOS system can be an equalizer.

See this article "Save our Sonics defense", which includes many video clips of the SOS defense. The SOS defense was integral in the success of the Seattle Supersonics in the late 80's and 90's when Bob Kloppenburg was an assistant.


Related pages:

Disclosure: This page contains affiliate links, which means that Coach's Clipboard receives a small commission (at no cost to you) if you make a purchase using these links.

Bob Kloppenburg's SOS Book and DVDs:


If you like the SOS defensive system, I recommend your purchasing the DVDs and book. The DVDs present the whole system very clearly and include demonstrations and descriptions of all the necessary, important drills, as well as on-court demonstrations... Coach Gels

Bob Kloppenburg's Sos Pressure Defense book - 4th edition

SOS Pressure Defense - 4th Edition, paperback, by Bob Kloppenburg

SOS Pressure Defense: Sequential Ongoing Strategies - Kindle version


Bob Kloppenburg's Encyclopedia of the SOS Defensive System

The Encyclopedia of the "SOS" Defensive System


Bob Kloppenburg's Advanced SOS Defensive System

Advanced SOS Defensive System