One of the things that I really agree with as far as defensive strategy is concerned with is to be flexible. Much more so than on offense, I think on defense you want to dictate the terms of how the game is going to be played. I was reading through some notes and I found this great article from Ghassan Sarkis who is the Lebanese National team coach and has coached professionally in Asia and the Middle East. In it, he talks about his philosophy on being adaptive on defense. Here is an excerpt,

With my years of experience, I have learned that a winning defense consists of several important questions that need answers: How do we play defense? Against whom do we play it? How do we “change” it from one game to another? At what time do we change our defense during a game? Many coaches believe in a single defensive strategy, and their own egos then become their enemies. Many good coaches feel the necessity of changing a defense, but they take no action. It is important to be flexible in your defensive strategy.

Here’s a prime example: In 1999, my Sagesse team was playing their first ever Asian Club Final against a Chinese team. On our road to the final, we only played man-to-man defense, but the Chinese team proceeded to pick apart and destroy our man-to-man defense. During the first half, they punished us with their pick-and-roll and accurate catch-and-shoot shots off the screens. At half time, we were down by eleven points. During the intermission, I briefed my players on their mistakes and how we should adjust our rotations. One minute before the jump ball to start the second half, I summoned the players and asked them to change over to a 2-3 zone. I followed my sixth sense and just “changed.” It turned out that our rivals could not handle the surprise, and we managed to win this very precious international trophy thanks to a defensive change.

This willingness to “adjust and change” a defensive strategy is what will bring victories. We double team today and we don’t tomorrow. We deny passes, we trap the low post, we switch on catch-and-shoot screening, we deny middle cuts. Then again, we do the opposite things in different games against different teams. In my philosophy, it is the opponent’s offensive strategy that determines my own defensive strategy for each game. My players are ready to adapt to different defensive tasks rather than being “programmed” to execute a single task. Offensive skills vary from one player to another and from one team to another, and thus these skills should be defended differently. Defensive strategies are being scouted exactly like scouting the player’s offensive skills. This gives us more reason to be unpredictable in our defense.

In our own defense, we also use many different strategies. Sometimes we double the post, other times we use full-court pressure, and at times use a junk defense. Much depends on who we play and the players we have on the floor. Sometimes we have players that play better M2M, other times we have great trapping players. We drill our players on all the fundamentals but in games, you must be adaptable.

For defensive fundamentals, Geno Auriemma is about as good as you can get to learn from. Coach Auriemma's new DVD on the four cornerstones of half-court defense shows you some great concepts in helping you establish a foundation in which your defense will be based on. I have the original Sarkis article as well as Geno Auriemma notes so be sure to check them out on the X's and O's Basketball Forum.