John this should cover it. It is both feet. Had this called a few times wrong by blue over the years.
LOOK-BACK RULE (Fast Pitch) (Rule 8 Section 7 T).
When a runner is legitimately off base after a pitch, or as a result of a
batter completing their turn at bat, and is stationary when the pitcher has
the ball in the circle, the runner MUST immediately attempt to advance to
the next base or immediately return to the base left.
The responsibility is entirely on the runner. There is no obligation on the
pitcher to look, fake or throw.
A. The “look back” rule does not go into effect for any runner until the
batter-runner touches first base or is called out, and the pitcher has
control of the ball within the eight foot radius circle.
B. Failure to immediately proceed to the next base or return to their original
base after the pitcher has the ball within the circle results in the runner
being called out.
C. Once the runner returns or stops at any base for any reason, the runner
is out if they leave that base.
EXCEPTION B-C: A runner will not be declared out when:
1. A play is made on another runner, or
2. The pitcher leaves the circle or drops the ball, or
3. The pitcher releases the ball to the batter, or
4. The pitcher places the ball under their arm or between their legs
to free both hands to fix their uniform, hair, etc. The ball is not
controlled unless it is held in the glove or hand. Once the pitcher
controls the ball again in the glove or hand, the “Look Back” rule
is again in effect.
D. If multiple runners are off base and more than one umpire calls a runner
out, the umpires must determine which runner was called out first
and return the other runner(s) to the base they left. When a runner is
declared out in this situation, the ball is dead. It is impossible to call
two outs on the “look back” rule.
E. A pitcher fielding a ball in the circle is an infielder and runners can leave
their base. If runners leave their base, the same rule applies while the
pitcher holds the ball in the circle: once the runner stops, they must
decide which way to continue or be called out.
F. A base on balls or a dropped third strike is treated as a batted ball if
the batter-runner continues past first base without stopping or stops
only once and then immediately moves one way or the other. However,
if the runner stops at first base and then steps off the base after the
pitcher has the ball in the circle, the runner is out.
G. Batter-runners overrunning first base can not start back to the base,
and before reaching first advance to second base. If a batter-runner
commits to first base, moving toward first base, the runner must return
to that base. The batter-runner may not change their mind and advance
to second base once they have started moving directly to first
base following the overrun. If they do so, the runner is out. Umpire’s
judgment determines what is committing toward a base.
H. If a runner is moving toward a base, other than first base, when the
pitcher receives the ball in the circle, that runner may stop once then
immediately advance to the next base or return to the previous base.
A runner failing to advance to the next base or return to the previous
base should be called out. Making an attempt or fake justifies the runner
being called out. If, after the pitcher has the ball in the circle, the
runner starts back to their original base or forward to another base and
then stops or reverses direction, the runner is out unless the pitcher
makes a play on them or another runner. When a play is made on any
runner, other runners may also stop or reverse their direction.
I. A runner is out when standing off the base and they do not immediately
attempt to advance or return after the pitcher has the ball in the
circle.
J. While in the circle and in possession of the ball, any act by the pitcher
that, in the umpire’s judgment, causes the runner to react is considered
making a play.
K. The pitcher must have control of the ball while in the circle. Placing
the ball on the ground, holding the ball between their legs or under
their arm is not considered having control of the ball.
L. Being in the eight-foot circle is defined as both feet within or partially
within the lines. The pitcher is not considered in the circle if either foot
is completely outside the lines.