rule 6.05(k)

[The Old Headbanger]

Hi there!

I would like to know how you interpret following line
of rule 6.05(k)
"being fielded to first base"
I ask because my native language is german.

and how would you rule this following situation.

bases loaded 1.out.
batter hits ground ball to short stop, the ss goes to the plate for force, the catcher is then throwing to first to complete the double play, while doing so the throw hits the runner who is not running within the 3-foot-line.

thanks for your help
Herwig
Salzburg/Austria