Marking, written by Chris Van Holmes

Marking is the action of defending the thrower. The marker has two
conflicting goals: harass the thrower into making a mistake, and
prevent a throw to a particular area of the field. The first goal is
predicated on team coordination to accomplish a turnover. This is
called establishing a force. The thrower is 'forced' by the marker to
deliver a pass to a particular area of the field while downfield
defenders attempt to deny receivers that area. The second goal relies
on individual effort by the marker to get a point block or stall. Both
can be highly effective.

The key to strong marking is in the stance. The proper stance affords
power and balance that you can use to respond to, or even anticipate,
thrower's actions. Spread your feet to about twice your shoulder
width. Bend at the knees, so the weight is on the balls of your feet
and your upper body is upright. Do not bend at the waist. This gives
you a center of gravity above the midpoint between your feet and the
leverage to move quickly in any direction. You want to be able to hop
left or right along with the thrower without having to change your
stance. Your arms should be out to your sides with the elbows tucked
in, hands low, and your fingers splayed.

This position uses your strongest, fastest muscle groups when you move
to attempt a block. You can quickly dart your hands to an unknown point
of release or shift your position to block a throwing lane. Exended
arms are harder to shift to the point of release and more easily
anticipated by the thrower. Most throws go underneath the marker's
arms. Until a thrower has beaten you with a high throw, keep your
weight low.

Once you have developed the proper stance, you need to practice moving
with the thrower. This involves maintaining your stance while hopping
to block the throwers potential release. Do not lunge, bend over, or
lift your feet into the air. All these actions ruin your balance and
limit your mobility. Use them only when the thrower is actually
releasing the disc and you are attempting a point block.

The next step is learning the proper reactions to a throwers movements.
There are only four basic moves: shift left, right, back, or forward.
If the thrower is attempting to throw into the deadzone the defender
must step back . This helps the marker defend by giving more time to
react to a pivot by or a released disc. It also prevents the thrower
from obtaining a free release behind the defender. The marker must
still remain active, shifting with the thrower as they attempt their
throws into the deadzone. As throwing skills increase, this job becomes
more difficult and the size of the deadzone shrinks. When the thrower
turns to the side, away, the marker must step up to reduce the size of
the throwing area and be in position to make a block. As the thrower
attemps throws to either side, the marker must shift right or left to
block the lanes.

After mastering of rapid shifts in position, you need to anticipate the
throwers intentions. There are many resources to draw on here. First,
be ready to respond to teammates requests. Second, use your peripheral
vision and ears. Third, recognize the throwers patterns. Fourth, get
inside the throwers head.

One advantage the marker has is always knowing where the thower will
be. Their pivot foot determines their location. The marker, however,
can be anywhere. If given free reign to harass the thrower, move
quickly and unexpectedly to different throwing lanes. Occasionally
don't respond to the throwers movements. If the thrower is expecting a
reation, this can throw him off stride.

When the marker is in a force defense, the primary is to prevent a pass
into the deadzone. The marker should remain in the throwing lane to
the weak side and still be very active. When the thrower attempts to
break the mark, back up into the throwing lane. This gives you more
time to respond to the throw and prevents the thrower from releasing
the disc past the markers body.

(The following paragraph is originally due to Jim Parinella.)
Another thing to help your marking is to learn individual thrower's
habits, such as noticing a penchant for the high backhand. We all have
our rivals that we play frequently, so notice the types of throws and
fakes the players you cover use. If they regularly throw over the
marker, be ready to take a step back to make this more difficult. If they
often step into the marker, be aware of that. If they always throw the
low inside out forehand, be ready for that. There is no one perfect
position to set up in. On some people you should set up as tightly as
you are allowed, on others, you want to back up a little.

You can also make adjustments for the weather. If it is windy, be sure
to stay low and force higher releases. This will expose the disc to
more wind and occasionally force unstable release angles