The diameter isn't 9 feet, it's the radius. The diameter is 18 feet.
"3.1 Around each goal there shall be plainly marked a circle known as the goal crease.
This circle shall be marked by using the mid-point of the goal line as the centre and drawing a
circle around that point with a radius of 9 feet (2.74 metres)."
That says 9 feet from the center point of the goal line, and that doesn't seem right either, Because when I'm in goal the top of the crease isn't 9 feet in front of me.