Evan Bourne, whose real name is Matt Korklan, recently did a shoot interview where he touched on the backstage altercation between Big Show and The Great Khali that took place while WWE was touring Puerto Rico in September 2009. Bourne admitted in the interview that he doesn't even think he saw it but they basically just ended up falling over some bags in the locker room because it was a small area.
You can watch his comments -- which contains language NSFW -- at this link or embedded below:
To recap, Big Show took issue with Khali using certain moves in matches that he felt were exclusive to him, as WWE's giant. Show threw a punch but tripped over some gym bags on the floor, which allowed for Khali to get on top of him. The fight was broken up shortly thereafter.