Can an outfield player go into goals for a penalty?
Is it considered a substitution?
Does he have to change shirts with the goalkeeper?
Finally an easy one...
Yes
No
No...but if he touches the ball on the ground inside the small square it is another penalty.
2.4 A penalty kick shall be taken from the ground
at a point 11m from the centre of the goal-line,
and only the defending goalkeeper may stand
on the goal-line. All other players, with the
exception of the player taking the kick, shall be
outside the 20m line and the arc, be at least
13m from the ball,