Hey,
I tested out the dev server and had a soccer ball with an indicator pointing straight to pvvnys room. So far so good - I threw the ball on the spot marked in the image:
http://imgur.com/a/MBWvF
However it blew up once it touched the ground - which was not quite what I expected. Not sure if thats intended.
Comments
Here is an old video (Apr 5, 2014) showing lobbing bombs into portal -
Here is an old video (May 30, 2014) jetpack into portal
Looks like i never bothered making one batting a soccerball, but it is similar to bomb.
You can read a long explanation about portals here, it'll make more sense.