I grew up in Utah and got to watch the Jazz basketball team just as they moved from New Orleans to Utah. They struggled for years but eventually picked up Adrian Dantley and some other great players. They were a fun team to watch and they started a new defensive strategy that hadn't really been used in the pros much until that time that I refer to as the funnel.

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The Concept of Defensive Funneling-HoopSkills.com
The Concept of Defensive Funneling
-by Coach Brian Schofield
http://www.hoopskills.com
I grew up in Utah and got to watch the Jazz just
as they moved from New Orleans to Utah. They
struggled for years but eventually picked up
Adrian Dantley and some other great players.
They were a fun team to watch and they started
a new defensive strategy that hadn't really been
used in the pros much until that time that I refer
to as the funnel.
Why do I call it the funnel? Simple . . . The team
would pressure as much as they could on the
outside to try to get the offensive player to take
the ball where the strength of the defense was.
For the Jazz, that strength was Mark Eaton.
Mark Eaton was a lousy college player for UCLA who hardly ever played. He had
average mobility and couldn't shoot a lick outside of a layup. However, Eaton
developed into a defensive force and a lot of it was the strategy the defense used.
While in college I had a coach who taught us to force the ball to the baseline and
another coach who taught us to force the ball to the middle of the court. I
wondered about both of them and I can see positives of both. What I realize today
is that each scheme should be based around the personnel of the team. The
theory behind forcing a player baseline is because it limits their options.
Players going baseline have to contend with the out of bounds line and have
limited court choices that they are presented with. Our team would force teams
baseline and then force a trap or bring help over and it worked very well with the
team we had. But if we had a shot blocker inside this wouldn't be my defense of
choice. For that I would pressure the ball completely and force a drive to the
middle or to the strength of the defense.

2. 2
The Concept of Defensive Funneling-HoopSkills.com
If I force them into a shot blocker then a number of issues happen. #1 I have my
best defensive player standing there protecting the rim. # 2 Intimidation. It's real.
Shawn Bradley (7 ft. 5 inches tall) blocked my shot once from 10 feet away from
me and I never shot around him again. #3 it’s easier to help. The middle of the
court is central and easiest to help out on.
If you watch football defenses you'll notice that they've used this concept for
years. They try to force plays to end up going to certain playmakers. For example,
the Ravens funnel as much as they can to Ray Lewis because he's one of the best
of all time. They like their chances there. The 49ers do the same with Patrick Willis
where they try to get the offense to bring the ball to him. It is no different in
basketball. Teams eventually would take whoever Mark Eaton was guarding and
stick him out near half court and just stand there. That way he would be out of the
key.
For young coaches, look at the talent you are presented with and plan a defense
accordingly. If you have a solid big man then it isn't a bad idea to really pressure
the ball and let the big man clean up underneath.