This is another article reposted from the uncbasketball.com by mikeness30. Hope it helps you in determining what is going on the next time you see a trap. I know it will help me.
One of the things I really see as a lost art in the modern college game is the trap itself proper when a team is either executing some sort of pressure defense of the zone variety and/or the man to man variety. So often you see teams who trap and the traps are easily split and/or they seem to come at the wrong times and are tried at very poor trapping places on the court.
One of the things I think more teams need to breakdown and practice is how to trap properly, in and of itself. One of the things we did in college, though we did not adhere to certain details as much as we should have, was to run three man trapping drills and start the ball handler out in the corner and he was going to try and get out of the impending trap while two guys would approach, one from the front and one from the side.
I think a better version of this drill would be to start your defenders like they were in a trap with a top man high and side man down further and make them approach the ball handler from the distances they would in a game. Far too often, I see coaches run drills that do not really recreate game like conditions in anyway, shape or form. The players gain nothing from this. Always remember, game spots, game speed.
There are two things that need to be stressed when teaching how to properly trap. The first thing that your kids need to understand is that stealing the ball or taking it from the defender is not the prime object. The second thing is that they need to learn to trap the ball, not the man. Getting your finger tips on the ball when it is passed or creating a very difficult situation is just as desirable as stealing the ball from the ball handler proper. One of the very bad tendencies that often comes with trying to steal the ball from the ball handler is useless and stupid fouls earned from reaching in wantonly.
When your kids approach the ball handler, first thing is that the man who is the top man on the press should approach when the man with the ball is dribbling away from him preferably towards the sideline. A top defender on the trapping defense should never approach until the ball handler is either looking away towards the sideline and/or faced up court and not looking back over the middle of the court. Both the top man and the wing defender on the ball side should angle slightly to force and/or invite the ball handler to try to head up the sideline.
One of the lost arts of trapping is using the sideline as a defender. Trappers should always be aware of this and like I said, I would position the top three men in such a fashion on any trap, You have your top man on the press angled and facing the ball handler, bouncing up and down with hands up and in the passing lane directly going to the middle. The trapper who is on the ball side and part of the two guards below the top man on the press should be back in about 5 steps off the sideline with his back to the middle and body angled towards the sideline, hands up bouncing and trying to get the ball handler to think that the sideline is the way to bring the ball up.
The bottom man on the top three of the press on the ball side has two jobs. The first I have stated and that is to try to force the ball handler to the sideline and the second job is to cut the ball handler off on the sideline once he gets him going in that direction. The top man on the press who is coming over to create the trap has one very, very important job and that is to contain the ball handler and to not let him bring the ball via the dribble back into the middle of the court and keep him over on that sideline.
One of the things you see a lot of these days is that once two trappers get a guy on the sideline, they immediately stand up and think they have the ball handler trapped but along the way someone forgot to inform the ball handler of this because he keeps his dribble and simply back dribbles and gets out of the trap. The trappers stand up as if the ball handler has picked up the ball and lose all of their ability to continue to move defensively and the trap is beat, the press is now beaten. The defenders have to remember their above listed responsibilities and play the ball handler as if they are playing man to man in the half court and you spring the trap once you get the ball handler to pick the ball up.
Two things to remember in trapping a man who has just picked up the ball. First thing, trap him quickly, do not sit back, look at each other and then a second or two later decide to put the trap on. Second thing the trappers have to do is to create a tall trap, mirroring the ball with their hands and locking their inside legs so that the man with the ball cannot split the trap which also is an oft occurrence these days it seems. It is imperative that the guys trapping remember to not break that "defensive plain" and to really mirror the ball the best they can while both of them yell out "dead, dead, dead" letting everyone else in the gym on defense know that the ball handler has picked up the ball and has been trapped. When a guy has the ball along the sideline either near or around the half court line, up in the corner after an inbounds or on the other side of the half court, for goodness sakes do not let him out of jail with a cheap reaching foul. Let the offensive man give you the ball, do not think it is necessary that you reach in and take it. Purpose of defensive pressure on both the full court and half court are something you have to establish in practice from day one.