The explanation for finals match 1 was "At the beginning of the match, one of the red robots drove onto a blue robot with the intent to inhibit that robot's actions", not quite high speed ramming. From watching the video here:
http://youtu.be/gCfHNWajGq4, I can't see anything like that, so it must have been off camera.
Edit: magnets beat me to it but I'll keep my post here for the video link.